BQM 334

    Keywords: Question

kb: This pattern occurs so often in my games that I want to find a good way to refute White 1 as Black in both diagrams (with and without the marked exchange in the second diagram). Does anyone know this pattern well enough to comment?

[Diagram]
Typical 4-4 joseki continuation  
[Diagram]
Typical 4-4 joseki continuation #2  

[Diagram]
Joseki  

Is this where you are coming from? If so, is the gain of B6 enough to sacrifice B2 with moves B8 at a and B10 at W9?

[Diagram]
Sacrifice  

Something like this?


Alex: I think peeping is one option, though it's liable to start a fight.

[Diagram]
White connects  
[Diagram]
White resists, Black fights  

zinger: Well, since you asked for comments, why does white play W9 here? It looks like it could be at B10, in which case B8 should probably be at a, and the fight will depend on the state of the upper left. In fact I think the state of the upper left is the key to this whole situation.

Alex: Sorry, I obviously whipped up this sequence too quickly and hallucinated... after Black b, W9, then W c is atari so Black has nothing here, you're right. Yes, B8 needs to be at a, so the fight is not good for Black, especially if White is strong in the upper left as he should be if he's playing this counter-pincer strategy. The compromise diagram is probably better; I think that unless White's hypothetical position in the upper left extends along the upper side as well, the strength White gets in that direction isn't out of proportion to Black's newfound central thickness and territory on the lower side.

(As an aside, as I said in the Discussion thread, I wasn't actually asking for comments, per se, though they are of course welcome... I was just wondering aloud whether Bill and Dave's silence meant that there was nothing wrong with my suggestions, or that there was everything wrong with them ;-) )

[Diagram]
White resists, Black compromises  

Of course, without the slide, you can peep on the other side if you like, in which case things get even hairier. (It should be fairly easy to see why you can't peep on this side if Black has made a slide.)


[Diagram]
White resistance  

Bill: Can White effectively resist with W7?


[Diagram]
The other peep  




[Diagram]
Hanging connection  

Bill: I think that B4 is a better way to connect.


[Diagram]
The other peep, part II  

Is the damage suffered by the marked stones worth the loss in the corner? Depends on the position, I'd imagine.

unkx80: Can't W3 be at B4? Then if Black plays at W3, then White a is atari.

Alex: Yup, same hallucination as in the other diagram. :-( I must have been tired that day.


[Diagram]
More typical joseki  

Dave: Let's assume that the sequence begins like this, which has been seen a few times in professional play. We further assume that W5 is played to take advantage of a White position at the top.

[Diagram]
More typical continuation 1  

Dave: Most often Black plays B1 here. It acts directly against White's desire to build up the top. If something like W2 then B3 strengthens the Black stones. Naturally this allows W4 but if B5 is sufficient for Black then not much has come of the original counter pincer.

[Diagram]
More typical continuation 2  

Dave: If White plays W2 immediately, Black could answer in the corner as above, but can also attach at B3 to take out the left side. W4 is painful but Black is not going to die in the corner.

[Diagram]
More typical continuation 3  

Dave: Black can also exchange B1 for W2 before jumping to B3. This does not protect the corner. Instead it leaves behind a defect at a to help the two Black stones if White sets out to capture them.


The preceding diagrams all come from professional play.

[Diagram]
The original question 1  

Dave: I did not find any professional games where Black simply played B1. In any case, now comes the exchange of W2 for B3 followed by the attachment at W4. White apparantly wants to connect the stones and the attachment is a typical tesuji for doing this. Should Black want to "refute" this? B1 here gives priority to the bottom side. This is a rather unusual follow up to the pincer, but that is another discussion :-) Playing B1 leaves the column of Black stone in the middle outnumbered 6 to 3 after W4. Black should not be thinking "refutation" but rather "reasonable".

[Diagram]
The original question 2  

Dave: My inclination would be to play B1-B9 here. This allows White to cut off 2 stones. However, those stones are not yet captured. Meanwhile Black has played on the bottom side and is pushing into White's upper left position. Remember that the basis for White's counter pincer is a White position at the top.


[Diagram]
The original question 2  

Bill: W2 puts great pressure on the black+circle stones. In addition, along with the white+circle stone, it guarantees that White can connect his groups with W4.

Black has already gotten himself into difficulty. Maybe B1 should have been at W2 or at a, as Dave indicates. Maybe a different pincer would have been better, or no pincer at all.

What to do next depends upon the rest of the board. Dave shows how Black can make a living group, but the time may not be ripe to do that. One temptation that should probably be resisted is to run with Black's weak group. It is often better, especially early in the game, to sacrifice weak stones, even if you give up more than you should have because of earlier mistakes. Maybe the best thing to do now is nothing. Tenuki is always an option.


[Diagram]
Rui - Aoki  

Bill: Here is a counter pincer from a game between Rui NaiWei and Aoki Shinichi. (See BQM 139.

[Diagram]
Go Seigen's recommendation  

Bill: Go Seigen recommends leaning on black+circle.

[Diagram]
Go Seigen's recommendation (continued)  

Bill: Note the turn, W3. Go Seigen points out that White is thick.


[Diagram]
Typical 4-4 joseki continuation #2  

Tapir: I am too weak to comment, but what do you think about this? B2 is afaik a technique to get B4 in sente, as B4 allows separating both groups, it may be what you want. Without black+circle in place the loss is too big after W5, but with it, why not?


BQM 334 last edited by tapir on November 17, 2010 - 20:33
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