Tesuji/Joseki question

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paK0
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Tesuji/Joseki question

Post by paK0 »

I just found this in 38 basic joseki, but I can't make any sense of it

I've tried a couple of lines, but I didn't get to one that doesn't end horrible for white.

Any help?

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DrStraw
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Re: Tesuji/Joseki question

Post by DrStraw »

Now what? Just push down at L3. Black cannot block without losing something.
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).
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Re: Tesuji/Joseki question

Post by Uberdude »

The important point here is that white wants to prevent black's groups from connecting, not save n2. If black captures n2 he hurts his k stones.
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Re: Tesuji/Joseki question

Post by paK0 »

Thanks for the answers, for some reason I though this would aim at the cut at O3
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Re: Tesuji/Joseki question

Post by drmwc »

Another point worth making is that the key thing for white to achieve is to separate black. The tesuji is a nice way of achieving this. However, an immediate block isn't disastrous:
Click Here To Show Diagram Code
[go]$$B
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . 5 . . . . . |
$$ | . . . . . . . . . 6 2 . . . . O . . . |
$$ | . . . . . . . . . 3 4 . . X . . O . . |
$$ | . . . , . . . . . 1 O . O X . , . . . |
$$ | . . . . . . . . . X 8 . 7 . . X . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
For example, 8 here is not a bad move. It may lose a couple of points relative to the tesuji but is an OK move. For example, next black may hane:

Click Here To Show Diagram Code
[go]$$B
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . . . . . . . O O . . . . O . . . |
$$ | . . . . . . . . . X O . . X . . O . . |
$$ | . . . , . . . . . X O . O X . , . . . |
$$ | . . . . . . . . . X O 6 X 5 . X . O . |
$$ | . . . . . . . . . 3 1 2 4 . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
We can compare this with a possible result after the tesuji:

Click Here To Show Diagram Code
[go]$$W
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . . . . . . . O O . . . . O . . . |
$$ | . . . . . . . . . X O . . X . . O . . |
$$ | . . . , . . . . . X O . O X . , . . . |
$$ | . . . . . . . . . X a 3 X 2 . X . O . |
$$ | . . . . . . . . . b 4 5 1 . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
If white later exchanges a for b, the result in the two diagrams is the same. So it's unlikely that the straightforward block loses too many points. (In fact, one can construct positions where it's the better move. However, white should probably play 3 in the last diagram at 4.)
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