This was an interesting game. Any comments would be appreciated. Some specific questions:

1. and were imitations of some moves I had seen commented once as over-concentrating black. So two questions: is black's result inefficient at the end? And can he change or to get a better result?
2. &ff. should be where I shine, but by it looks very bad for me (I think.) So two more questions: what would have done the job better? And does this imply the ogeima was too loose?
3. Is a mistake? Any general ideas for when to pull out cutting stones, and when to move elsewhere?

Any thoughts on the rest of the game welcome, of course.

[deleted]

Hmm interesting.

As to 41:
Yeah you're stronger in the general area, but you have a few specific weaknesses you have to take care of if you want to keep the opponent weak.

Black definitely did not suffer during the sequence played, and he tore through your corner and gained thickness in the center while you salvaged a bit on the bottom edge.


So lets try to rethink to 41: You have a large knight's move enclosure. It has lots of aji in it even without opponent's stones. so with them, it's getting a bit weak - so you pretty much have to defend the corner, and lo and behold, not only do you get a nice corner, but also black is left with a weak group he has to take care of.

The exact method of defense in this case should be a topic of another post... But any form of defense on the corner formation is better than the game continuation IMO.

Yeah....very interesting. I cannot say for sure that it is a good sacrifice. My gut feel is that you got the better of it after he played 11 at R6.

I do think that black could do much better with 11 at R4. There is way too much aji left when he plays at R6. Not only did it make a very useful ko threat for you later, but a quick superficial read suggests that it can live ( at the expense of letting black build a wall which will require white to reinforce his lower middle stones. )


How much is a tenuki at 33 worth?

42 looks better at D4. Because of the high white stone on the lower side, and the aji of the lower right, the bottom is going to be trash. It does not profit you to invest much effort making territory there.

dinner...gotta go...maybe more later

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A few comments on the early part of the game:

and look like an interesting strategy, no idea if this is good or not. B needs to add another move, but my choice would be R4, to eliminate the corner aji.

The fight W started around move 20 does not look reasonable. at D18 is joseki. could have ended the game by atari at D18.

at K17 is a very small extension, with no offensive or defensive meaning, in an uninteresting direction, where little territory is at stake. If B ignored this move to extend to C8, he would have a much better position. The difference between a B stone at C8 and a W stone at C9 or C10 is much larger than mere territory, affecting the safety of both the left B group and the loose W corner enclosure. Fortunately B answered with an equally small extension, so W got the first move on the left.

ignored a direct B threat, letting B break through and split the corner shimari. Defending at D4 or D5 was necessary. After either of these two moves, B would have no easy continuation, and W could fight with confidence in this area. The two W stones to the right should not get into trouble -- as B plays to settle the E5 stone, W should get natural opportunities to defend and even attack. The only dangerous attack by B is M4, but that seems premature while B has weak groups to the left. Even if cut off, the O4 and R5 stones have enough aji for W to do something in the corner, so this B territory is far from secure.

A bit redundant; I post slowly.


Edit: May also want to think about playing your N4/M4 stone low.

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Hi there,

I didn't like W124. This saves 2 stones which are relatively unimportant, but allows black to cut off K17 which ultimately turns into a large black area.

I'd rather G17~ or something of the like, which makes points along the top. Let Black have those 2 stones in gote if he wants them.

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Thanks for all the comments, guys.

@joaz: I guess the question about tenuki at is whether my is sente or not. Tenuki away from a sente sequence strikes me as unduly aggressive. Maybe he can make some probes, but I think black needs to come back to fix those cutting points pretty soon. Right?

on the sequence in the upper left: black needs various ladders for most reasonable variations, the most important of which he didn't have, and others of which he would need to ignore important ladder-breakers.

on the lower left: well, it seems that I don't know anything about defending ogeima's. D4, D5, and for that matter E4 I rejected as being too close to the lonesome enemy stones. But I guess I should have thought of it more as a forcing move than an invasion.

@mitsun: I'm surprised that you don't like (the k17 extension). There are eight spaces between B and W on the top, and 4 spaces between B and W on the left. Further, it seemed to me that if B got k17, his position would become rather deep and it would be impossible, for example, to profitably invade the upper right corner. In fact, in reviewing I wondered whether maybe (c9) was a mistake, since I was never able to figure out any way to threaten B with it... When you say c9 is more interesting and has more territory at stake than k17, do you mean purely in terms of the relative safety of the lower left and the center left, or is there more to it than that?

@aurik: agreed, :w124: was bone-headed.

@loons: thanks for all the detail! very helpful.