Joseki deviation

Bill Spight · #1

The first joseki book I got was about joseki deviations. I still think that that's an excellent approach to joseki study.

Black has deviated from joseki and made very small life in the corner. How may White take further advantage?

Enjoy!

--- From Igo Sokusei: Kokon Muhi (囲碁速成 : 古今無比), vol. 2, by Tsutsumi Tatsujiro (堤辰二郎), 1894.

moyoaji · #2

Is there a specific move sequence that is suggested or does the book just talk about a rough idea?

I can't see any one move that would be ideal in all situations, but I think I get the general idea of how white can proceed.

It would seem that black has a floating group and a lone stone that have been separated by the white group in the middle. That means black has 2 weak groups near each other while white has only one. And anyone who can count to 2 in go can win a lot of games.

Other stones on the board do matter, but it would seem that white should begin to attack these groups as he moves his own group out toward the center. This shouldn't be much of a problem as any move white picks to move his group toward the center will attack both black groups. Then, since black can only defend one group at a time, white can just attack the one black didn't defend while he becomes stronger.

The B15 group seems pretty solid so I wouldn't be too worried about that coming under attack. All white has to worry about is the D17 group while black has two problems on the board.

Bill Spight · #3

moyoaji wrote:

Is there a specific move sequence that is suggested or does the book just talk about a rough idea?

White already has an advantage, but there is a move that leaves Black in a terrible plight.

Edit: Hmmmm. Actually, upon reflection, I think that things are not so bad for Black. But White has a cool move, anyway.

mitsun · #4

EdLee · #5

Bill Spight wrote:

From Igo Sokusei: Kokon Muhi (囲碁速成 : 古今無比), vol. 2, by Tsutsumi Tatsujiro (堤辰二郎), 1894.

Hi Bill, thanks! How did you come across this book? (Is it out of print now?)

Kirby · #6

Bill Spight · #7

EdLee wrote:

Bill Spight wrote:

From Igo Sokusei: Kokon Muhi (囲碁速成 : 古今無比), vol. 2, by Tsutsumi Tatsujiro (堤辰二郎), 1894.

Hi Bill, thanks! How did you come across this book? (Is it out of print now?)

From Japan's National Diet Library. Online access at http://dl.ndl.go.jp/info:ndljp/pid/861038

Bill Spight · #8

The book only gave two variations, both beginning with E-13. It also shows a similar position arising from the three space pincer, where White plays the shoulder blow against the pincer stone. That implies that the shoulder blow against the two space pincer is too close.

One of the variations is the same as one of Kirby's, but continues a few moves further. The other one follows one of Kirby's, but instead of sacrificing five White stones, has a tesuji to save them. The tesuji is interesting, but IMO Kirby's sacrifice is better.

Upon reflection, I now think that Black should sacrifice his four stones instead of capturing the White stones. Here is the SGF file for all this.

Kirby · #9

Interesting discussion, Bill.

I keep thinking about this position:

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

vs. this position:

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

The influence in the first diagram is magnificent - I would prefer white in that situation, especially in the beginning of the game.

In contrast, the second diagram doesn't let white get such magnificent influence, but it a couple of costs:
* 10 points from black's capture in diagram A + 8 points in black capture in diagram B = 18 points from the respective sacrifices.
* In Diagram A, black has sente, whereas in Diagram B, white has sente.

It's hard to say what the value is of the next sente play, but thinking of only the point differential above, I ask myself if the difference in outside power is worth 18 points between the two diagrams. I think it probably is. In Diagram B, white's group is pretty safe, but will be more difficult to utilize from other parts of the board than in Diagram A. Difficult thing about this type of analysis, is that evaluating the power of the white wall in Diagram A vs. the outside situation in Diagram B cannot be performed precisely, since it depends very much on the future of the game.

Still, my feeling says that the outside power is worth the gote and the point difference. If nothing else, it'll make for an enjoyable middle game :-)

Joseki deviation

Who is online