In which loons loses a reverse-sandbagging game (? vs 1k)

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In which loons loses a reverse-sandbagging game (? vs 1k)

Post by Loons »

Hey,
Playing as a 1d? I lost by 1.5 points against this 1k taking white no komi ... After he let me get ahead (recover...) in the early-mid-game, I managed to... Solidly lose very many points in yose. I would be thankful for peoples' comments, especially on yose - if you could give me some examples of sente sequences I should have taken, that would especially be great.



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Re: In which loons loses a reverse-sandbagging game (? vs 1k

Post by illluck »

I think a lot of the yose errors (e.g. it seems like P18 should have been taken by you first, L2 was quite small, a few aji-keshi moves after the F14 cut) are just because you were in byoyomi.

However, one sequence which started on move 114 at Q16 really jumped out at me. Not only is Q16 sort of a weaker shape, it was also aji-keshi. Doesn't P16 instead look better? Black can no longer try to save the two stones since any attempt will really damage the right side/corner.
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Re: In which loons loses a reverse-sandbagging game (? vs 1k

Post by Loons »

Thanks. I guess time management earlier is also part of endgame strength...

This is sort of what was happening in my head, incidentally, I just clicked the wrong place when I tried to play it -_-

Could you give a short sequence to demonstrate from P16 instead?

Click Here To Show Diagram Code
[go]$$Wc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X O . . . . . . . . . . . X . . . |
$$ | . O X O . O . . . . O O . O O . X . . |
$$ | . X O , . . . . O , . X 3 X 2 O X . . |
$$ | O X O . O . . . . . . . 5 4 1 X . . . |
$$ | . O X X X . . 7 . . . . . 6 . . . . . |
$$ | . O . . . . . . . . . . O . . . . . . |
$$ | . . X . . . . . O . . . . . X X X . . |
$$ | . . X O X . . . O O . . . O X . . X . |
$$ | . . X O X . . X O X X . . . O X X . . |
$$ | . . O X . . . X X O . . . O O O O . . |
$$ | . . O X . X . . . O . . . O X X . O . |
$$ | . . . O . O . . . O . . . . . . X X X |
$$ | . . O . . O X X . . . . . . O X . O . |
$$ | . . . . . X . X O . . . O . O X . . . |
$$ | . . . O . X . X O , O O X . X , . . . |
$$ | . . O . . X X X X O . X . X . . X . . |
$$ | . . . X X . . . O . . . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]




PS: I am also already vaguely aware of how terrible a move G1 was
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Re: In which loons loses a reverse-sandbagging game (? vs 1k

Post by illluck »

Ah, hehe. Your new sequence makes a lot more sense (though then black can O15 instead after 1, I think).

I was thinking wP16, then if black tries to run with O15 white can push through twice and then R16.

I must admit, though, that I missed 1 - if black can't O15 then your diagram is a better result (because if wP16 bP15 white can only N15, which ends in gote whereas your sequence ends in sente/H7 - though I would be a bit concerned about aji around N14).
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Re: In which loons loses a reverse-sandbagging game (? vs 1k

Post by illluck »

Also, I think black missed a chance at move 145 - H15 seems harder to deal with.
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Re: In which loons loses a reverse-sandbagging game (? vs 1k

Post by mitsun »

I like yose, so let's see if we can convert your 1.5 point loss into a 10+ point win :)

118-123) turned out very badly. It would be much better to give up the W stone at Q16 in order to capture the B stone at M16, by playing move 118 at N16. Compared to the game, B gains something like 8 points in the corner, while W gains more than 12 points in the center.

132-139) forcing moves really gained nothing, because of your shortage of liberties, and B missed a chance to make the result even worse (atari before defending). Maybe just defend quietly at H14?

154) should be the large monkey jump to F1. B then cannot get an eye at the bottom, hence must connect above in gote. In the game, B made an extra point and eye at the bottom, then connected unnecessarily above, when larger moves were available (notably b7 atari).

180) was very small, 1 point gote at most. D6 and S9 were each 4 points gote. You could consider these moves miai (although B later got both). O5 was at least 2 points reverse sente.
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Re: In which loons loses a reverse-sandbagging game (? vs 1k

Post by Numsgil »

Just got done re-reading a book on contact fights, so, with some things still fresh in my newbie mind, I've commented on some positions. Not really yose-related, though...

Click Here To Show Diagram Code
[go]$$Wc
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . 1 . . . . . . . . . . . . . |
$$ | . . . . . X O . . . . . . . . . . . . |
$$ | . . . O . X O . . , . . . . X , . . . |
$$ | . . O . . X . . X . . . . . . . X . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


This is an overplay, or at least inconsistent. If you want to save the two white stones, you need to extend once more to gain liberties (you want 5-6 liberties before you make a new group with a hane, generally). If you want to sacrifice the two white stones, it probably would be better to play something like this:

Click Here To Show Diagram Code
[go]$$Wc
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . 7 5 . . . . . . . . . . . . |
$$ | . . . . . 3 4 6 . . . . . . . . . . . |
$$ | . . . O . 2 1 . . , . . . . X , . . . |
$$ | . . O . . X . . X . . . . . . . X . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


If you want sente, treating black 1 above as a forcing exchange and moving elsewhere would make sense, too. Though it would be a bit bland as a forcing move since black gets more than you do, really.

What you played in game started with 'I'm making a wall' and ended with 'I'm sacrificing these stones', so ends up feeling wishy-washy and irresolute.

Strategically, I think continuing the wall is preferable to sacrificing. Black is invadable enough on the right that a wall could be useful, and white's wall facing the left side doesn't do much against your strong position there. But this is more of a gray area I'm not totally comfortable with just yet, so I'm less certain about that.


Click Here To Show Diagram Code
[go]$$Wc
$$ +---------------------------------------+
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . O . O O . X . . |
$$ , . . . X . , . . . |
$$ . . . . . . X . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . b X X c . |
$$ . . . . 1 a O O d . |
$$ , . . . . . , . . . |
$$ . . . . . . . . . . |
$$ . . . . . . X . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ , . . . . X , . . . |
$$ . . . . . . . X . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ +---------------------------------------+[/go]


One of 'a', 'b', 'c', or 'd' (well, 'd' is stupid) would be the normal choice in this position, since they would increase liberties and/or keep up pressure on the opposing white stones. 'a', then a 1 point jump would be consistent with what you're trying to do but without the added aji you left behind.

If you were trying to play lightly, then R11 was inconsistent with that. I'm not sure what the light shape would be here, though.


Click Here To Show Diagram Code
[go]$$Wc
$$ +---------------------------------------+
$$ | . . . . . . . . . .
$$ | . . X O . . . . . .
$$ | . O X O . O . . . .
$$ | . X O , . . . . O ,
$$ | O X O . O . . . . .
$$ | . O X X . . . . . .
$$ | . O . . b . . . . .
$$ | . . X a . . . . . .
$$ | . . 2 1 4 . . . . .
$$ | . . X O X . . . . ,
$$ | . . O X c . . . . .
$$ | . . 3 d . . . . . .
$$ | . . . . . O . . . .
$$ | . . O . . O X X . .
$$ | . . . . . X O . . .
$$ | . . . O . X O . . ,
$$ | . . O . . X . . X .
$$ | . . . X X . . . . .
$$ | . . . . . . . . . .
$$ +---------------------------------------+[/go]


This feels like an inconsistent sequence. White 1 above says you want to save those stones, but white 3 says you're sacrificing them (since if you go 'a', black goes 'b' and catches you in a net (although with some more reading I'm not totally certain the net work work if white plays 'c' after the 'a' and 'b' exchange. Maybe white should try and escape and make a fight of it?)). Sometimes enlarging a sacrifice is preferable if you can get more liberties than the opposing player can take away in a single move, since you'll get extra forcing moves. I can buy that that is the case here. But with that idea, taking the sente exchange at 'd' before taking sente elsewhere seems important (urgent even), since if you let black take 'd' (which you do later), you have to respond (so it's really double sente) and your enlarged sacrifice doesn't give you all the forcing exchanges it should, so white 1 above was a waste (would have been better off just not making it).


Otherwise most moves jived with my understanding. Which makes sense since this was a relatively high level game :)
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