BQM121

  Difficulty: Intermediate   Keywords: Life & Death, Question
[Diagram]
White lives  

Snotnose: In a recent handicap game, this sequence almost occurred.



White neglected to play W10 and a black move there killed the corner. However, backing up a bit, should White be able to live here?

[Diagram]
Can White live?  

If Black had played B1 here instead, the sequence in the previous diagram would not work for White.



I fail to see how White can live. Can she?

[Diagram]
Essence of shape  

Backing up further, here is the essence of the shape.



In the diagrams above, Black had made some forcing moves to disconnect W1 and W3 from the corner. I show this shape to raise the more general question about what variations exist for Black here. B4 was played to coordinate with a Black star point stone in the upper right. Prior to this game, I had not seen the W5-W7 combination before so I had to invent a strategy on the fly. I opted to seal off W1 and W3, thinking I'd then kill the corner. But, had White not made an error, the corner would have lived. Was Black's strategy sound? Should the corner die if it is disconnected from W1 and W3?


[Diagram]
 

At a glance, W1 looks like the vital point here. After B2, the 1-2 points are miai and I can't see a way for White to live.

[Diagram]
 

Maybe W3 and W5 ? Doesn't look like it. (have to go) -- Zook

[Diagram]
White dies  

Andre Engels: To understand more of zook's comments, please note that in the game sequence, black could have killed white with the combination of B3 and B5. I myself would have played B2 in zook's first diagram at B4, but it seems that both moves kill.

[Diagram]
 

Thanks André, i had forgotten to come back. So here's the completed second diagram. W9 is necessary to make an eye around B4, but then B10 makes leaves a and b as equivalent. --Zook


Charles This is a known way for White to play, at least in a handicap game. As I recall, Kitani liked it. (I have had a bad experience playing it with White, though.)

[Diagram]
Shape  

There is a concealed point about shape here. Black's play at black+circle is quite good.



[Diagram]
Black aims to cut  

Next Black can aim at the B1+B3 combination, putting White into trouble.



Thanks Charles. So if White insists on living in the corner, I suppose one might expect the following.

[Diagram]
White lives in corner  

Black might finish off by playing a for a very thick position. Depending on the position, perhaps a could be omitted for now. Notice that black+circle is very well placed, allowing Black to run white+circle to the edge. This partly explains the value of this two space low pincer. A more or distant or higher one would not work as well.


BQM121 last edited by Unkx80 on April 17, 2004 - 21:44
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
RecentChanges
StartingPoints
About
RandomPage
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Goproblems.com
Login / Prefs
Tools
Sensei's Library