Approaching first before taking the open corner as white?

Hades12 · #1

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . a . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 9 . . | $$ | . . . . . . . . . . . . . . . 0 . . . | $$ | . . . 2 . . . . . , . . 8 . 4 , 3 . . | $$ | . . . . . . . . . . . . . 6 5 7 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

After this this sequence, is it okay to leave the lower right, for white to take the upper left corner 'a'? I played this in one game and got a good result, but I am curious as to your opinions as to whether or not this is an even/good exchange for white. It feels like blacks five stones in the BR are not very efficient compared to white. White is getting around the board quicker.

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 2 . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . O 1 . . | $$ | . . . O . . . . . , . . O . O , X . . | $$ | . . . . . . . . . . . . . O X X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

I was experimenting with breaking up the mini-Chinese/orthodox opening.

Kirby · #2

Well, from the other thread, the hanging connection is not necessarily sente compared to a solid connection, so black may take the last corner:

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 9 . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . b . . | $$ | . . . 2 . . . . . , . . 8 a 4 , 3 . . | $$ | . . . . . . . . . . . . . 6 5 7 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

If

is at 'a', it'd be harder to ignore, because of the attachment at 'b'.

With the hanging connection, 'b' isn't really that severe, since :w4:

stone is weaker, I think.

Bill Spight · #3

From AlphaGo Teach ( https://alphagoteach.deepmind.com )

Click Here To Show Diagram Code: [go]$$Bc Hanging connection inferior $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 9 , . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 2 . . . . . , . . 8 . 4 , 3 . . | $$ | . . . . . . . . . . . . . 6 5 7 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

loses 3.3% points in winrate. :b9:

plays in the top left corner.

Click Here To Show Diagram Code: [go]$$Wcm8 Extension inferior $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 3 . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 2 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . 1 O , X . . | $$ | . . . . . . . . . . . . . O X X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

White plays the solid connection, :w8:

, instead of the hanging connection. Then :b9:

loses 3.1% in winrate. :w10:

takes the 4-4 in the top left corner.

Click Here To Show Diagram Code: [go]$$Bc Solid connection not sente $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 9 . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 0 . . | $$ | . . . 2 . . . . . , . . . 8 4 , 3 . . | $$ | . . . . . . . . . . . . . 6 5 7 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

After the solid connection, :w8:

,

plays in the top left corner, then :w10:

attaches in the bottom right.

Uberdude · #4

Of course you can approach before taking an empty corner, but you should be prepared for your opponent to play well and ignore and take an empty corner instead of obediently answering all your approach and subsequent moves! 5 attach is ok because high approach is slack territory so there's a good reason to immediately 'punish' it (empty corner good too). 6 ok, 7 ok, 8 should be solid to make followup after tenuki better, 9 should tenuki to empty corner, 10 is probably better in empty corner so black doesn't have a chance to seek sente and get it himself, 11 is slack, if you are going to answer then o5 first (if white connects then you can answer, maybe s7 not solid, and you made white heavier so when he tenukis to empty corner next the pincer is better, and if white push up at n5 then black can tenuki and white push and cut doesn't work so well anymore) is a lesson from AlphaGo vs Lee Sedol game 2 (AlphaGo's early peep was only good because Lee was obedient, stronger versions of AG see that the peep is not good because black should resist). 12 tenuki to corner is good, white has gained a little, but only because the sum of black's mistakes was more than the sum of white's.

Hades12 · #5

Bill Spight wrote: