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Joseki question (4-4 approach, pincer, 3-3 invasion)
http://lifein19x19.com/viewtopic.php?f=12&t=13661		 Page 1 of 1
Author:  Gotraskhalana [ Sat Oct 08, 2016 1:02 pm ]
Post subject:  Joseki question (4-4 approach, pincer, 3-3 invasion)
On the left of the following diagram is a joseki question. On the right, White played in the other order. Can Black now play the triangled stone? Or is the cut too dangerous? Or does it depend if there are other stones nearby?

Click Here To Show Diagram Code
[go]$$B
$$ -------------------------------
$$ - . . . . . . . - . . . . . .
$$ - . . . . . . . - . . . . . .
$$ - . 6 O 2 . 8 . - . 4 O 6 Y .
$$ - . 4 1 X 3 . . - . 2 1 X . .
$$ - . 5 7 . . . . - . 3 5 . . .
$$ - . . O . . . . - . . O . . .
$$ - . . . . . . . - . . . . . .
$$ - . . X . . . . - . . X . . .[/go]
Author:  Uberdude [ Sat Oct 08, 2016 1:27 pm ]
Post subject:  Re: Joseki question (4-4 approach, pincer, 3-3 invasion)
Something to bear in mind even if the cut isn't a problem for black is that white can also clamp. In that case descend is for sure an overplay for black (without nearby support) so he would just need to connect and white connects under. That result is worse for black than joseki because he made a bad push into the gap. This is bad for several reasons: it wastes a ko threat, loses a liberty, and most importantly perhaps it loses other options in that position such as placement at 4 after the checking extension on the side (a).

Click Here To Show Diagram Code
[go]$$B
$$ +------------------
$$ | . . . . . . . . .
$$ | . . . . 4 . . . .
$$ | . O O O 1 2 . a .
$$ | . O X X 3 . . . .
$$ | . X X . . . . . .
$$ | . . O . . . . . .
$$ | . . . . . . . . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ | . . . , . . . . .[/go]


Also by playing that hane first white gives back a chance to switch direction like this (next maybe a or b):
Click Here To Show Diagram Code
[go]$$W
$$ +--------------------
$$ | . . . . . . . . . .
$$ | . 3 4 . . . . . . .
$$ | . 5 O 2 . . . a . .
$$ | . 1 X X . . . . . ,
$$ | . . . . . . . . . .
$$ | . . O b . . . . . .
$$ | . . . . . . . . . .
$$ | . . X . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . , . . . . . ,[/go]


I'd probably just extend.
Author:  Gotraskhalana [ Sat Oct 08, 2016 2:32 pm ]
Post subject:  Re: Joseki question (4-4 approach, pincer, 3-3 invasion)
Thanks, I didn't think about the clamp at all.
Author:  EdLee [ Sat Oct 08, 2016 10:35 pm ]
Post subject: 
( Diagrams rotated for space. )

If :b3: = :bt: hanes first (instead of the joseki extend),
one could revert to some of the mentioned variations:
Click Here To Show Diagram Code
[go]$$B var 1
$$ -------------------
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . O 1 . O . X .
$$ | . . 2 X . . . . .
$$ | . . 3 . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]
Clamp:
The mentioned clamp :w8: :
Click Here To Show Diagram Code
[go]$$B var 1(a)
$$ -------------------
$$ | . . . . . . . . .
$$ | . . 6 4 5 . . . .
$$ | . . O X 7 O . X .
$$ | . . O X . . . . .
$$ | . . X . . . . . .
$$ | . . 8 . . . . . .
$$ | . . . . . . . . .[/go]
Mentioned: peaceful, but B not as good as joseki:
Click Here To Show Diagram Code
[go]$$B var 1(b)
$$ -------------------
$$ | . . . . . . . . .
$$ | . . O O X . . . .
$$ | . . O X X O . X .
$$ | . . O X . . . . .
$$ | . 0 X 9 . . . . .
$$ | . . O . . . . . .
$$ | . . . . . . . . .[/go]
Mentioned: messy fight depends on the surroundings:
Click Here To Show Diagram Code
[go]$$B var 1(c)
$$ -------------------
$$ | . . . . . . . . .
$$ | . . O O X . . . .
$$ | . . O X X O . X .
$$ | . . O X . . . . .
$$ | . 9 X 0 . . . . .
$$ | . . O . . . . . .
$$ | . . . . . . . . .[/go]
Descend:
W also has the option to drop to :w4:
Click Here To Show Diagram Code
[go]$$B var 2
$$ -------------------
$$ | . . . . . . . . .
$$ | . . 4 . . . . . .
$$ | . . O X . O . X .
$$ | . . O X . . . . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]
Peaceful:
Click Here To Show Diagram Code
[go]$$B var 2(a)
$$ -------------------
$$ | . . . . . . . . .
$$ | . . 4 6 . . . . .
$$ | . . O X . O . X .
$$ | . . O X . . . . .
$$ | . . X 5 . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]
Reference: if B blocks the other side directly:
Click Here To Show Diagram Code
[go]$$B var 3
$$ -------------------
$$ | . . . . . . . . .
$$ | . . . . . 4 . . .
$$ | . . O 2 . O . X .
$$ | . . 1 X 3 . . . .
$$ | . . . . . . 5 . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

Also peaceful, but W better than joseki:
Click Here To Show Diagram Code
[go]$$B var 2(b)
$$ -------------------
$$ | . . . . . . . . .
$$ | . . 4 5 . . . . .
$$ | . . O X . O . X .
$$ | . . O X . 9 . . .
$$ | . . X 6 7 . . . .
$$ | . . 0 8 . . . . .
$$ | . . . . . . . . .[/go]
B collapses:
Click Here To Show Diagram Code
[go]$$B var 2(c)
$$ -------------------
$$ | . . . . . . . . .
$$ | . . 4 5 0 9 . . .
$$ | . . O X . O . X .
$$ | . . O X 8 . . . .
$$ | . 7 X 6 . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]
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