TesujiFromAmateurGames2/Attempts

[Diagram]
Shape point?  

Alex: Looks to me like Black has a number of good options. I would probably instinctively play B3 immediately, but since you say it's a tesuji problem, something more clever is probably in order.

B1 looks like a shape point to me, and White doesn't seem to have anything better than this sequence, which helps Black enclose a lot of territory in the left-centre. After W10, the safe move is a, and Black's lead is enough that safe moves are probably the best plan.

tderz: Cutting point a is indeed a problem to be resolved in gote.
This sequence is not correct.

"instinctively play B3 immediately" ... amazing!
Many people would descend to B2. Could you elaborate further on B3 ?

[Diagram]
Non shape point?  

ilan: My instinct says to play B3 here.

[Diagram]
3 dan instinct  

Alex: Well, the original reason I said B1 here would be instinctive to me is that it threatens ladders at both a and W4. However, when W responds at W2, if Black plays at W4 immediately, White at B3 would be sente, so this isn't acceptable.

I still don't think B1 is bad, though, because after Black blocks at B3, even if White exchanges W4 for B5, she'll have trouble pulling out her cutting stones and they won't have much value, since Black is strong enough on both sides. Meanwhile, Black will probably get to force at b or c, which is rather painful for White.

tderz: Alex, you correctly conclude, deduce that W2 here is not the proper shape. The later W4 is aji keshi for the cutting points.
White will not play this way. (W2 above)

[Diagram]
Chinese 7 dan instinct  

tderz: Chinese 7 dan, German 3dan instinct calls for ...(a basic shape move)

I could write it here, but simply suspect that you are still online.
[Diagram]
Table point?  

[10]Alex: If White plays the table point at W2, Black can attach at B3 and crosscut with B5. There are many variations after this, but most of them seem to start a fight that is unreasonable for White because of Black's thickness on the left, so White does not seem to have anything much better than W6, which lets Black make a lot of territory, albeit in gote. I don't think there's any need to capture White's marked stone at the moment.

White's result would be slightly better in endgame terms if she played atari at B9 before capturing with W6. However, then Black would have the option of starting a large ko by resisting with a. I haven't taken the time to count threats, so I don't know whether it's worth the risk for White.

tderz:

  • B5 is good (part of the solution)
  • B7 is aji keshi, finding something better is the solution.
  • W6 first at B9 is not possible - without ko
  • I think there is a great need for controlling cutting points in the only moyo vs. a 7-dan ("capturing White's marked stone" = honte).

Alex: My thinking behind B7 instead of b is that b will still be sente later, since the follow-up is about 10 points sente, so maybe it's best to keep it around as a ko threat. However, that was assuming that Black would take gote and connect at B9. If the plan is to tenuki, I guess you probably need b first, or else whatever tesuji you have in mind for the next problem may not work.

[Diagram]
no ko  

tderz: basically Black gets B9 without ko. This is big.
Of course, it's better to exchange first -c-d-e before that (ko).


[Diagram]
a dubious idea? (W6 above W4)  

[20]zinger: At a glance, I considered B2 the obvious move, and indeed I'm still not finding much better. Here is one other possibity I thought of, but I have my doubts about it - white is more likely to play W8 at a, B9 at b, then c, and black doesn't seem to have accomplished much. I'm looking forward to the solution.

[Diagram]
W2 - "Connect your own stones"  

tderz: [30] How about W2 here? ("Connect your own stones, leave the cutting points to the other.")
If B3 at k, white could create a triple miai (o, m or around n) with l or j.


[Diagram]
Hanazuke  

Bill: B1 is a kind of tesuji, but is it aji keshi? After W2 White can respond with W4 to B3. The side is larger than the four black+circle stones, no?

Although after B5 - B9 it's a difficult fight.

tderz: I agree Bill. Black needs 2 moves a+b (tempo) to connect B1 to the rest, this while already 1 white move a would be sente (of course this would be aji-keshi too).

White f+g form very bad geta-aji against Black B3 here (if he wanted to resist too much).

[Diagram]
ladder aji - (keshi)  

tderz: a white stone on circle severely erase this ladder aji here.

[Diagram]
shape  

tderz: Despite that the ladder aji is gone after B1, White will still play this W4 here (safe).
White does not need to extend to e (unsafe), because Black has a (double) open skirt (W4+o).

So, my original question was meant to be:

  • how to continue after W4?
    • (exchange B1-W2 can be left out)




Conclusions

During the game I thought that the variation [10] (with a little difference, cf. /solution is the solution.
Now I am not so sure anymore.
Because [20] is so bad for white, she cannot allow it and will play [30], which ends in gote and therefore has lots more aji than [10], but is slightly bigger.
If one was 90% sure ("pretty sure") to handle the aji and knew the score (I knew neither :-( ), then one could play [30].


TesujiFromAmateurGames2/Attempts last edited by tderz on August 17, 2005 - 11:07
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