It shouldn't surprise me any more I guess that my opponent has found another move that I didn't consider at all. The first move that came into my head was C15, but then I decided I liked the look of B15. I'm now also thinking about D15. I haven't even decided on my move as I start to type this, but hope that doing so will bring some clarity to my thoughts and allow me to discover which move I prefer.
So, let's consider what happens if I play C15. Black will
surely play B15 (otherwise I see no point at all in his last move) - and, other than having sente, I can't say I like the result very much - Black is alive, with more points than I would want, and can push out (or perhaps even hane at C13) from his corner. What is more, that cut at D15 now seems to work, as black at D14 is now an atari, so I may well need to make yet another move to defend here, and I'll have achieved none of the aims I wanted from this corner situation. Thus I'm going to rule out C15.
What about B15, then? The advantage of this is that it succeeds in cutting black's just-played keima, and also leaves a lack of eyespace in the corner, forcing Black to run. The downside, if such it is, is that the continuations are very messy (I have learned my lesson for next time topazg!). Given how complicated it is, and how many unexpected moves DIV has made, I'm not going to give many variations, but here is one sequence I can envisage:
$$Wc robinz vs DIV - Move 22; prisoners: Black 0 White 1
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . X O . O . . . . . . . . . . . . . . |
$$ | . . X O . X . . . . . . . . X . . . . |
$$ | . 4 X O . . . . . , . . . . . , X . . |
$$ | . 1 2 6 . . . . . . . . . . . . . . . |
$$ | 5 X O . . . . . . . . . . . . . . . . |
$$ | . 3 . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . O . . O . . X . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Wc robinz vs DIV - Move 22; prisoners: Black 0 White 1
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . X O . O . . . . . . . . . . . . . . |
$$ | . . X O . X . . . . . . . . X . . . . |
$$ | . 4 X O . . . . . , . . . . . , X . . |
$$ | . 1 2 6 . . . . . . . . . . . . . . . |
$$ | 5 X O . . . . . . . . . . . . . . . . |
$$ | . 3 . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . O . . O . . X . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
- actually looking at the position makes me like this less than I thought I did; the problem is Black's move 4 here, which makes an eye in sente (OK I can play at A16 to stop it becoming an eye, but after BA17 WA15 black has yet another move to cause me problems), thus still allowing Black to run. Meanwhile my stones are cut to pieces and lacking in liberties. D18 isn't even an eye yet, although I could make it so by playing at E17 next. On the other hand, Black still can't obviously link up to the F17 stone, and if I can surround and capture it quickly I should be OK. But while I'm doing that Black can either cause all kinds of chaos with the group running out from the corner, or simply play big points elsewhere.
So my conclusion about this move is that it's a lot better than C15, but it gets into a big messy fight (such situations being one of the weaker parts of my game), which may well not be that favourable - so I'm not going to make it unless I really dislike the result from D15.
As for D15, it seems to be the obvious move for a nice quiet life. But I don't think I can keep sente - Black will obviously play at C15, and I have another cut to worry about at D14. The best way of handling that looks to me to be the following:
$$Wc robinz vs DIV - Move 21
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . X O . O . . . . . . . . . . . . . . |
$$ | . . X O . X . . . . . . . . X . . . . |
$$ | . . X O . . . . . , . . . . . , X . . |
$$ | 2 . X O . . . . . . . . . . . . . . . |
$$ | . X O . . . . . . . . . . . . . . . . |
$$ | . 1 . 3 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . O . . O . . X . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Wc robinz vs DIV - Move 21
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . X O . O . . . . . . . . . . . . . . |
$$ | . . X O . X . . . . . . . . X . . . . |
$$ | . . X O . . . . . , . . . . . , X . . |
$$ | 2 . X O . . . . . . . . . . . . . . . |
$$ | . X O . . . . . . . . . . . . . . . . |
$$ | . 1 . 3 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . O . . O . . X . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
(2 could of course be at a couple of other places as well; what's important here is that some move there needs to be played). The good news is that Black is sealed in and I'm conected - the bad news is that black has sente (as well as a couple of potentially annoying peeps for later - indeed the one at E14 looks already quiet effective, if it's followed up by E15 or F15).
Oh - but what if Black plays B15 instead of C15? It looks very small and passive, and I will have sente, but Black won't be sealed in any longer. I can't hane - I can quietly extend, and am more than happy for Black to crawl along the second line will giving me a third line wall, but of course Black won't do that and will take his sente elsewhere. Or I could just take sente, and let Black try to make things complicated again with B13 or C13.
Well, that's a choice I won't have to make until later, and I think I prefer any of these outcomes to the messiness of the B15 option. Hence I've decided on D15.
Far less headaches! Don't take this as a criticism at all as it isn't - it's always fun when things get into complicated-land to have a look-see and think whether it could have been avoided.
), as it threatens to kill Black's group - but for this very reason I would much rather keep it in reserve as a ko threat. (In fact, if it comes to a ko fight and I'm after threats here, I think playing one at B17 first will yield a second ko threat.)
)