I had an opponent deviate from joseki, allowing a fairly severe punishment. I thought it might be an interesting problem for maybe 6k players.

Click Here To Show Diagram Code

[go]$$Bm1
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . 3 4 6 . 2 . .
$$ | . . O 5 1 . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

Click Here To Show Diagram Code

[go]$$Bm7
$$ ------------------
$$ | . . . . . . . . .
$$ | . . 6 a . 2 . . .
$$ | . . X O O 1 O . .
$$ | . 4 O X X 5 . . .
$$ | . . 3 . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

is not joseki - it should be at a. Black to punish the error!

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KGS 4 kyu - Game Archive - Keyboard Otaku

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Someday I want to be strong enough to earn KGS[-].

Black can get more.

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KGS 4 kyu - Game Archive - Keyboard Otaku

i dont see any more. i am really curious how.

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"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

This is what I had in mind. Maybe I'm wrong?

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KGS 4 kyu - Game Archive - Keyboard Otaku

Thats what I would have played.

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Why not play 13 at 17? This is the normal way to play if you can, as white cannot answer differently so he ends up with worse shape.

I guess that is a little better. But the point is that white gets sealed in on both sides, which isn't possible in the joseki line.

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KGS 4 kyu - Game Archive - Keyboard Otaku

Doesn't White end up with better shape this way? That looks like a failed A-B-C principle to me

It is not obvious to me that this is the case.

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

Click Here To Show Diagram Code

[go]$$Bm7
$$ ------------------
$$ | . . . . . . . . .
$$ | . . 6 . 8 2 7 . .
$$ | . 0 X O O 1 O a .
$$ | . 4 O X X 5 . . .
$$ | . 9 3 . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

In this diagram, wouldn't it be better to play white 16 at a, thus giving up two stones and avoiding being shut in?

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If you say no, Elwood and I will come here for breakfast, lunch, and dinner every day of the week.

That's what herman is saying I think entropi.

Oops my question was already answered by an earlier post Sorry, I should have read it more carefully, I just looked at the diagrams.

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If you say no, Elwood and I will come here for breakfast, lunch, and dinner every day of the week.

not really.. what herman is saying is ..16 & 17 exchange is an aji keshi that only helps black cover his weakness. although endgame point of view it is not optimal but in the opening part of the game it is better not playing optimally. black is not going to play 16 anytime soon because it is an aji keshi so there is no point playing endgame that only expose your weakness.



16-17 exchange will coverup the weakness at 'a'

Click Here To Show Diagram Code

[go]$$Bm13
$$ ------------------
$$ | . . . . . . . . .
$$ | . . O . 2 O 1 . .
$$ | . . X O O X O 3 .
$$ | . O O X X X . . .
$$ | . 4 X a . . . . .
$$ | . . 5 . . . . . .
$$ | . . . . . . . . .[/go]

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

Actually, that was what I was saying in the text above my diagram.

Also, it's probably good to play this exchange anyway, even though it removes aji, because otherwise:

Click Here To Show Diagram Code

[go]$$B
$$ ------------------
$$ | . . . . . . . . .
$$ | . . O . O O X . .
$$ | . . X O O X C X .
$$ | . O O X X X B . .
$$ | . 1 X . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

If black ever captures the white stone with (e.g. white played a ladder breaker) then becomes sente:

Click Here To Show Diagram Code

[go]$$B
$$ ------------------
$$ | . . . 5 . 7 a . .
$$ | 6 2 O . O O X . .
$$ | . 1 X O O X C X .
$$ | 3 O O X X X B . .
$$ | . X X . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

Now, white can't ignore the capture and play tenuki with , because then and kill. As long as a is still atari (i.e. before the capture of white stone at ), black can't kill, but:

Click Here To Show Diagram Code

[go]$$B
$$ ------------------
$$ | . . . 5 . . 6 . .
$$ | 8 2 O . O O X . .
$$ | . 1 X O O X O X .
$$ | 3 O O X X X 7 . .
$$ | . X X . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

This is a rather painful way to lose a ladder breaker.

So all in all, White should usually just play the exchange in the original diagram, even though it is aji keshi a little.

Rolling back a few moves ...

Click Here To Show Diagram Code

[go]$$
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . O . . .
$$ | . . X O O X O . .
$$ | . 3 O X X 2 . . .
$$ | . . 1 . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

When black plays 1, is it feasible for white to capture with 2? For ease of viewing it would look like this:

Click Here To Show Diagram Code

[go]$$
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . O . . .
$$ | . . X O O . O . .
$$ | . X . X X O . . .
$$ | . . X . . . . . .
$$ | . . . . . a . . .
$$ | . . . . . b . . .
$$ | . . . . . . . . .[/go]

True there is a loss in the corner, but white is much thicker than in the joseki. It seems like this might be playable in an approriate whole board position.

Next white can take sente to play elsewhere, or locally jump to a or even b.

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Main Entry: zing·er Pronunciation: \ˈziŋ-ər\
1 : something causing or meant to cause interest, surprise, or shock
2 : a pointed witty remark or retort

I think that it is feasible, although the loss in the corner is quite big, so the sente has to be worth it.

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A good system naturally covers all corner cases without further effort.

Kogo's lists that as a joseki variation, but it's Kogo's.

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KGS 4 kyu - Game Archive - Keyboard Otaku