Please take a look at sgf and please share your thoughts about it.
I have a little problem with a joseki below. There is some trick variant which is quite hard for me to evaluate and to come up with a good solution.

[edit]
I corrected some coordinates mentioned in eidogo diagram.
Changed a subject line a little

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Shouldn't w p15 be at p17?

If p17 then he would be tricked (black move #9 is a first trick move) and black's corner is bigger than in a correct (joseki) way of playing.

I wonder where you first learned that W P15 is the correct answer. I do not agree with that. The following is normally considered a joseki.

Click Here To Show Diagram Code

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

Now only the position of changes. In my opinion the position is worse for black because of the aji. For example, if white gets 'a', there is a big yose 'b' left, which is not the case in the first diagram. Also white has at least 5 big ko threats in the corner which is not good for black.

Click Here To Show Diagram Code

[go]$$c This is worse for black
$$---------------------+
$$ . . . . . . . . . . |
$$ . . . . . 8 7 3 9 . |
$$ . 0 . . . 6 1 O 4 . |
$$ . . . . . O 2 X . . |
$$ . . . . . . 5 . b . |
$$ . . . . . . . X . . |
$$ . . . . . . . . . . |
$$ . . . . . . . a . . |
$$ . . . . . . . . . . |[/go]

I know it from Alexander Dinerchtein's article about trickplays. And yes, you are right about ko threats and weakness left behind but these are very subtle things, too subtle as for my taste.

Click Here To Show Diagram Code

[go]$$c a sugested trick continuation by AD
$$---------------------+
$$ . . . . . . . . . . |
$$ . . . . . . 5 X 3 . |
$$ . . . . . 4 X O O . |
$$ . . . . . O O X . . |
$$ . . . . . 2 1 . . . |
$$ . . . . . . . X . . |
$$ . . . . . . 6 7 . . |
$$ . . . . . . 8 . . . |
$$ . . . . . . . . . . |[/go]

trick continuation looks good for white if... black choose to play . But if he plays at 4 then it turns to be rather difficult. As I mentioned in eidogo diagram, I managed to get a good result and win a game but I'm still thinking how to play harder in this kind of position.

[My "solution" with a stupid missread... A ladder... thx macelee]


What do you think?

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As you suggested the situation is quite tricky. We need stronger players to explain this for us.

But what you proposed in the diagram clearly doesn't work because black can P14 and then O15 to kill the 3 stones in ladder.

May I suggest the following:

Click Here To Show Diagram Code

[go]$$c So, how about this
$$---------------------+
$$ . . . . . . . . . . |
$$ . . . 6 5 7 . X 9 . |
$$ . . . . 4 3 X O O . |
$$ . . . 8 . O O X . . |
$$ . . . . . 2 1 . . . |
$$ . . . . . . . X . . |
$$ . . . . . . 0 . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]

I think strong players should prefer the play outside at early stage of games.


A variation - black still needs to go back to the corner. This of course assume the ladder is favourable for white (white chose to play this whole thing so that is not a problem).

Click Here To Show Diagram Code

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

has no choice, because:

Click Here To Show Diagram Code

[go]$$c need one move in the corner
$$---------------------+
$$ . . . . . . 6 . 5 . |
$$ . . . O X X . X 4 . |
$$ . . . . O X X O O . |
$$ . . . O . O O X 2 . |
$$ . . . . . O X 3 . . |
$$ . . . . . 1 . X . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]

On eidogo, the reply to the trick seems to be Q18.

how this could happen

Thank you for your solution, looks very nice.

@Alguien - thanks for information about Q18, but the outcome is not the best for white in my opinion. Next M16 for black will be sente (I'm reffering to kogo's joseki solution) and black will have a nice follow up on right side still threating a white central stones. It's not clear if white will have a chance to attack.

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I knew we already had a thread about this, so now I found it and I think this post (viewtopic.php?p=65417#p65417) is quite helpful to answer your question.

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