Page 7 of 33

Re: Prokovich game

Posted: Wed Aug 25, 2010 7:08 am
by Chew Terr
Emerald: If that happens, could white build up strength by pushing the right down and then invade to the left?

Click Here To Show Diagram Code
[go]$$Bcm17 Obvious choice?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 3 . . |
$$ | . . . . . . . . . . . . . . . 6 7 . . |
$$ | . . . . . . . . . . . . . . . 4 5 . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . 2 , . . . |
$$ | . . O X X . . 8 . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Prokovich game

Posted: Wed Aug 25, 2010 7:09 am
by Kirby
I'd probably play P4 as emeraldemon suggested. Another possibility is P3. I feel a little bit like P3 is lax, though, since M3 is present.

Re: Prokovich game

Posted: Wed Aug 25, 2010 7:48 am
by Tooveli
Chew Terr wrote:Emerald: If that happens, could white build up strength by pushing the right down and then invade to the left?

Click Here To Show Diagram Code
[go]$$Bcm17 Obvious choice?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 3 . . |
$$ | . . . . . . . . . . . . . . . 6 7 . . |
$$ | . . . . . . . . . . . . . . . 4 5 . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . 2 , . . . |
$$ | . . O X X . . 8 . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


I know my name is not Emerald but I think I can answer this.

Click Here To Show Diagram Code
[go]$$Bcm17 What do the circled stones do?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . W X . . |
$$ | . . . . . . . . . . . . . . . W X . . |
$$ | . . . O . . . . . . . . . . . . X . . |
$$ | . . . O . X . . . , . . . . Q , . . . |
$$ | . . O X X . . 8 . X . Q . . . . Q . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


The white triangle stones are already quite strong. I don't think the circled stones really add much to the attack and they help Black connect and give him more aji in the corner while also weakening R11.


My thoughts.

I liked freegame's idea for move 17, but I didn't like the way it let White potentially get the big move at C13. I would have suggested C12 directly and, if not that, then R9. I think (with hindsight) Black approached at the bottom right because C12 directly makes it very hard to invade the lower right after White R14 (or maybe Q6). Playing R5 instead of R9 allows Black the chance of getting sente.

Click Here To Show Diagram Code
[go]$$Bcm17 Hard for Black to get sente
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . c . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . a . . |
$$ | . . . O . . . . . . . . . . . . b . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


If Black plays a, then White can tenuki and take c (which seems huge). If Black plays b, then White can wedge and either get a better results locally or get sente for c. So I think this is why Black changes the order.

Click Here To Show Diagram Code
[go]$$Bcm17 Black gets sente?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 4 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 3 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . 2 , . . . |
$$ | . . O X X . . . . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


If White answers naturally at 18 then Black exchanges 19 for 20 and gets to play 21.

Having said all this I'm starting to consider a pincer for White's next move. The pincer didn't naturally occur to me because of how unusual it is with 3-3 as Black has a strong followup in the corner. I still can't quite see one working so I stick with my last diagram as my prediction.

Re: Prokovich game

Posted: Wed Aug 25, 2010 10:15 am
by Joaz Banbeck
As Tooveli has already suggested, letting black live easily on the right side is good for black. Following that logic, I consider an approach from above to be forced:

Click Here To Show Diagram Code
[go]$$Bcm17 White's next move
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


But then the question naturally arises: if white's move is this good and this obvious, why would black play :b17: there in the first place? Surely, as a pro, he can see :w18: coming.

And he can see what it looks like if he runs:

Click Here To Show Diagram Code
[go]$$Bcm17 A bad sequence for black
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . 5 . 3 . 1 . . |
$$ | . . . O . X . . . , 6 . . . . , . . . |
$$ | . . O X X . . . . X . O . . 4 . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


If he attaches as Chew inquired about, white just slides under to connect M3.

Click Here To Show Diagram Code
[go]$$Bcm17 Another bad sequence for black
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . 7 5 3 O . . |
$$ | . . O . . . . . . . . . . 8 6 4 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


All of these look better for white. So what is black up to?

My anwer to this is derived by a long and twisted route. It starts with an observation by Topazg and maybe others that black has a weak spot:

Click Here To Show Diagram Code
[go]$$W
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . W . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Black has several obvious ways to fix this. None of them look good.

This is too slow and over concentrated:

Click Here To Show Diagram Code
[go]$$W
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . B . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]



This encourages the parallel response from white, and white gets more from the exchange than black:

Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . 1 . 2 . . . . . . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Black would like to have this problem go away without resorting to slack moves like the two above. The best solution that I can see is to keep white's M3 stone weak - or even kill it.

Black would like to do something like this:

Click Here To Show Diagram Code
[go]$$B P3 may be just as good
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . 1 . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]



But that just leads to this, and black has to take a move to defend his lower left group, and it ends up looking good for white:

Click Here To Show Diagram Code
[go]$$B I'm not certain about exactly where 4 goes
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . 3 . 2 . . . . . . . |
$$ | . . . O . X . . . , . . . . 4 , . . . |
$$ | . . O X X . . . . X . O . 1 . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


So I've been pondering sequences like those above, noting that black would like to play something like O3 or P3 without the natural white response at M5 being available. Then I see black make a move that makes no sense by itself.

My conclusion is that black's R5 is a sacrifice, and that he is going to make a double attack on the corner like this:

Click Here To Show Diagram Code
[go]$$Bcm17
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . . 3 . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


...or this:


Click Here To Show Diagram Code
[go]$$Bcm17
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . 3 . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


...or this:



Click Here To Show Diagram Code
[go]$$Bcm17
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . 1 . . |
$$ | . . . O . X . . . , . . . 3 . , . . . |
$$ | . . O X X . . . . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


One of the things that I am not sure about is how easy is it to attack a 3-3 stone, even with two approach moves?
The following are speculations:

Click Here To Show Diagram Code
[go]$$Wm20
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . 1 . . . 8 X . . |
$$ | . . . O . X . . . , . . . . . 7 5 6 . |
$$ | . . O X X . . . . X . O . . X . O 4 . |
$$ | . . O . . . . . . . . . . . . . 3 2 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]



Click Here To Show Diagram Code
[go]$$Wm20
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . 1 . . . . X . . |
$$ | . . . O . X . . . , . . . . 7 , 5 6 . |
$$ | . . O X X . . . . X . O . X . . O 4 . |
$$ | . . O . . . . . . . . . . . . . 3 2 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Prokovich game

Posted: Wed Aug 25, 2010 1:14 pm
by dfan
Click Here To Show Diagram Code
[go]$$Wcm18 ACTUAL GAME: Move 18
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . X . . |
$$ | . . . O . X . . . , . . . . a , . . . |
$$ | . . O X X . . . . X . O . . . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

The commentary says that White a, Black 18 would have been good for Black.

Re: Prokovich game

Posted: Wed Aug 25, 2010 6:17 pm
by Magicwand
Click Here To Show Diagram Code
[go]$$Wcm18 ACTUAL GAME: Move 18
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . X . . |
$$ | . . . O . X . . . , . . . . . 3 . . . |
$$ | . . O X X . . . . X . O . . 2 . O . . |
$$ | . . O . . . . . . . . . . . . . . 4 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

it's been 20 years since i studied japanese professional game. i think next few sequence is above...

Re: Prokovich game

Posted: Wed Aug 25, 2010 6:26 pm
by dfan
Magicwand wrote:it's been 20 years since i studied japanese professional game. i think next few sequence is above...

Do you think this game is Japanese?

Re: Prokovich game

Posted: Wed Aug 25, 2010 6:39 pm
by freegame
Joaz Banbeck posted almost every possible follow-up. :o
My guess is the same as one of his suggestions.

my thoughts:
White :w18: seems likely. This wil stabalize the white stone on the left while putting pressure on the black invasion.
Black can not jump to a. That would be too soft. White would then build points at the bottom while attacking the black stones.
Therefore black needs to find something else. Splitting the bottom seems like a nice idea. This makes use of the bottom group black already has.
After :b19: it gets quite complex. Both have weak stones, but they seem to be equally weak. Therefore I think this is better than :b19: @ a.
Joaz Banbeck wrote:
or this...
Click Here To Show Diagram Code
[go]$$Bcm17
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . a . 1 . . |
$$ | . . . O . X . . . , . . . . . , . . . |
$$ | . . O X X . . . . X . O . 3 . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]



Re: Prokovich game

Posted: Wed Aug 25, 2010 6:41 pm
by mitsun
I think Joaz has the right idea -- B will play for a trade like that shown below. I prefer B1 here better than one space to the right, as it captures W more cleanly.


Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . 4 X . . |
$$ | . . . O . X . . . , . 5 3 . . 2 . . . |
$$ | . . O X X . . . . X . O . 1 . . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Prokovich game

Posted: Wed Aug 25, 2010 6:44 pm
by freegame
@ mitsun

provided that up to :b1: is the actual game,
don't you think they will put up more of a fight?
It seems very passive to each take one side...
I also like black in your diagram, so I guess white
will start a fight somehow, and not allow what you suggested.

Re: Prokovich game

Posted: Wed Aug 25, 2010 6:59 pm
by mitsun
freegame wrote:@ mitsun
provided that up to :b1: is the actual game,
don't you think they will put up more of a fight?
It seems very passive to each take one side...
I also like black in your diagram, so I guess white
will start a fight somehow, and not allow what you suggested.

Yes, it is unlikely to proceed so simply, but I think this is what B is aiming for, so I think B1 will be the next move. After that, I don't think W can permit B to play at W2, so some splitting move like W2 seems necessary. After that, all other bets are off :) (However, I do think the peaceful diagram I showed is fair for both sides, partly because the captured W stone still has more aji than the captured B stone.)

Re: Prokovich game

Posted: Wed Aug 25, 2010 8:37 pm
by Magicwand
dfan wrote:
Magicwand wrote:it's been 20 years since i studied japanese professional game. i think next few sequence is above...

Do you think this game is Japanese?

yes! chinese and korean player do not play double 3-3 point.
i only saw them in japanese game 30 years ago.

Re: Prokovich game

Posted: Wed Aug 25, 2010 8:51 pm
by emeraldemon
Magicwand wrote:
dfan wrote:
Magicwand wrote:it's been 20 years since i studied japanese professional game. i think next few sequence is above...

Do you think this game is Japanese?

yes! chinese and korean player do not play double 3-3 point.
i only saw them in japanese game 30 years ago.


Hmm... Yi-Setol played it against An Cho-yeong not that long ago:

[sgf-full]http://www.lifein19x19.com/forum/download/file.php?id=325[/sgf-full]

This isn't the game we're reviewing tho. For what it's worth, he lost that game.

Re: Prokovich game

Posted: Wed Aug 25, 2010 8:58 pm
by Joaz Banbeck
freegame wrote:Joaz Banbeck posted almost every possible follow-up. :o


:lol: I was trying to illustrate a general idea of the proper direction of play. The important thing was not the exact location, but the line of reasoning that leads to that location.

After finding some time to examine the details, I like this one best:

Click Here To Show Diagram Code
[go]$$Bcm17
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . X . . |
$$ | . . . O . X . . . , . . . a . , . . . |
$$ | . . O X X . . . . X . O . 3 b . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


'A' is too high, and white slides underneath. 'B' is too close and gets run over, I think.

Re: Prokovich game

Posted: Wed Aug 25, 2010 9:09 pm
by Magicwand
Joaz Banbeck wrote:
freegame wrote:Joaz Banbeck posted almost every possible follow-up. :o


:lol: I was trying to illustrate a general idea of the proper direction of play. The important thing was not the exact location, but the line of reasoning that leads to that location.

After finding some time to examine the details, I like this one best:

Click Here To Show Diagram Code
[go]$$Bcm17
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . . . |
$$ | . . X , X . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . X . . |
$$ | . . . O . X . . . , . . . a . , . . . |
$$ | . . O X X . . . . X . O . 3 b . O . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


'A is too high, and white slides underneath. 'B is too close and gets run over, I think.


i read all the reasoning...
but i have this feeling that move 19 is wrong.
i dont know why i get this feeling and can not explain what is wrong with this move.
maybe someone stronger can explain why i get this feeling.