Shape Problem 4 / Discussion

Sub-page of ShapeProblem4
Black needs to correct this shape  

Charles Matthews My first comment here is that the shape relationship between black+circle and black+square is never really good.

DaveSigaty: I think that we have to add white+circle into the mix before we can try to claim that the black+circle - black+square relationship is not really good. When the White stone is missing, it is the standard (5-6 times more frequently played than any alternative) choice for closing the corner.
Abstract pattern (1)  

In this case black+circle and black+square have a good relationship.

DaveSigaty: With both white+circle and white+square on the board the play at black+circle does not have a very successful record. While the theoretical relationship may be nice, it is too passive. When jumps to W1, the corner is still vulnerable. Black will likely want to add B2 anyway. At this point is he better off with the stone on black+circle?
Abstract pattern (2)  

And also in this case black+circle and black+square have a good relationship.

So you could say that Black has created himself a shape problem, by taking 50% from each pattern.

In this case:

The 'big bulge'  

I recommend on general grounds this 'big bulge' shape made of two keima.

HolIgor: We have a winner. This is what I meant.

White cannot lean  

A play at a becomes impossible.

Corner aji  

Maybe there are still 3-3 invasion problems at a after black+circle. Black could try a play like b to keep the corner.

Playing black+circle, however, seems to get Black out into the centre in good shape. So it looks like good style to me.

Jan: This was my first idea too, but Charles was quicker[1] (but then, I haven't written a book on shape :-). One thing I wasn't sure about was whether the correct solution really keeps white separated. What happens after the following moves? W3 seems to be able to reach the upper-side group.

White trying to connect  

White trying to connect  

Karl Knechtel: I'm not convinced of that. (5-8 are shown to indicate that a counterattack is futile.)


Charles Not in the book, and of course I cheated with a database (I wouldn't enjoy posting comments without some sort of verification). But 'big bulge' is a term from Shape Up!

Shape Problem 4 / Discussion last edited by KarlKnechtel on August 18, 2003 - 05:12
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