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You don't think that 'y' is White's sente?Kirby wrote:I'd like to clarify something regarding this comment, which I don't get.
Here, white takes gote. But a play at 'x' is white's privilege - it's sente for white, but gote for black.
So later in the game, we can assume that white will get to push: So that will be the final position.
Contrast this with the hane: is playing at 'y' white's privilege? I'm not so sure.
Well, that throw-in variation makes White saving his group sente. And a large sente, at that, worth about 25 points. The variation where Black tenukis and allows White to continue with the jump to "y", makes White saving his group gote. If the jump to "y" is sente, that gote gains only about 17 points. But it is true that I did not work out the White follow-up after "y". I assumed that it was worth more than 8 points, because the Black area is open, and because of my knowledge of the value of another one space jump on the edge in more enclosed situations, and because the traditional value of the monkey jump agrees with my calculations. But I did not calculate the follow-ups, and the follow-ups after that, etc., which would have been necessary to get a precise value. Your objection has made me reconsider. One thing is that, because the Black territory is open, Black does not have as good a reply to the jump to "y" as when the territory is more closed. So maybe the jump to "y" is not sente, because it has gained so much already.If things play out as suggested with the throw-in variation that was provided here, this was the final variation:
Black has one more point at 'w' in this variation, and the option of later taking the ko.
I don't understand how we can assume the jump at 'y', above, since it's not clear to me that this is black's privilege, given the throw-in variation.
So I don't completely understand the comment that the sagari is 7-8 points less than the hane. It only makes sense to me if we assume the jump at 'y', but I don't see how this will happen given the throw-in variation.
Maybe the White follow-up gains only 6 points or so. (I hardly think it can gain less. My admittedly imperfect influence function estimates the gain at about 8 points. It assumes that all the stones are alive, which does not seem too far off base here.) Anyway, on the assumption that the jump to "y" is gote, with a follow-up that gains only 6 points, the hane gains about 16 points instead of 17 points. The hane is still clearly better than the sagari, and it is gote. AfterKirby wrote:Well, I don't know if 'y' is sente or not. I was confused because I thought the throw-in variation was the better one, and if so, the sagari is not worse than the hane since it reduces black by more points on the top.
But it sounds like you're saying that the throw-in variation is worse since it lets white live in sente. I suppose that's true, but it's not intuitive to me since black captures white's hane stone.
Also, I wasn't objecting so much as asking for clarification. I know almost nothing about the endgame.
White is alive, right?Yeah, I don't dispute that it's alive in sente. Maybe I just didn't realize why it was a bad variation. For example, if black just leaves it: I don't know if white will get the jump at 'y' or if black will get the block at 'z'. Maybe the point is, since 'y' is probably sente, we can assume white will get 'y'?Bill Spight wrote: After
The last diagram is gote, not sente.Kirby wrote:Yeah, I don't dispute that it's alive in sente. Maybe I just didn't realize why it was a bad variation. For example, if black just leaves it: I don't know if white will get the jump at 'y' or if black will get the block at 'z'. Maybe the point is, since 'y' is probably sente, we can assume white will get 'y'?Bill Spight wrote: After
Intuitively, it seems that black's followup to 'z' is sente, so it would be most likely that black would get 'z'.
If that's the case, I'd compare this diagram for the hane: to this variation for the descent: The descent is easier for me to understand, since the ko isn't involved, so maybe I'm not making a fair comparison.
True. It lives in gote.Bill Spight wrote: The last diagram is gote, not sente.
If White doesn't answer, Black kills.Kirby wrote:I guess there's also the situation where there is no throw-in at all:
I guess black should probably play at least 'y', because if white ignores to play sente somewhere else, black captures the hane stone in sente.
So if black plays 'y', white can either answer or not answer:
1.) If white doesn't answer, black captures the hane stone in sente,
Yes, good pointBill Spight wrote:
If White doesn't answer, Black kills.
Well, the two are similar in that regard. What's most unclear to me is the throw-in variation with the ko. If black has ko threats, practically speaking, it seems black may be able to block at 'y' in sente.Uberdude wrote:Kirby, if you have doubts about the one space jump after ignored hane being sente, why do you think push after your descent is sente?
Hmmmm, you still seem to be confused. So if white hanes then if black blocks directly white is still not alive (a17 still kills, the exchange didn't help white):Kirby wrote:Well, the two are similar in that regard. What's most unclear to me is the throw-in variation with the ko. If black has ko threats, practically speaking, it seems black may be able to block at 'y' in sente.Uberdude wrote:Kirby, if you have doubts about the one space jump after ignored hane being sente, why do you think push after your descent is sente?
But I guess I think it's more likely that white lives in sente since black has to eventually take the ko.
I guess I lean toward thinking the hane is better than descending, but I can't say I have my head wrapped around the position.
, is obviously correct. is incorrect. But it duplicates the position in the first diagram, which indicates that 
in that diagram is wrong.Oh, I don't doubt it!Uberdude wrote: Hmmmm, you still seem to be confused.
Since the ko situation is not clear to me, it's not clear to me that black has to defend at the marked stone in the position above.Uberdude wrote: Usually black doesn't need to worry much about the ko cut, because taking the ko is sente for him to kill the corner, so it likely ends up looking like this after he takes the ko and later white takes back and black defends. So black closed the top, but took gote to do it. It's like you decided to defend the cutting point after diagram 2, but maybe another move is bigger.