robinz wrote:Yet another surprising move from MHO. I had trouble deciding between this simple capture and the cut at E6. Playing the former, I expect white to play at E6 to connect his groups, then I get sente to play elsewhere (M17, almost certainly). Whereas, playing E6 now, I would expect white to capture at A5 himself - then, as far as I can read I need to play another move in the corner (looks like the hane at E1 kills, to me), but then white needs B8 (or similar) to save his own left-hand group, and once again I have sente. So the only question is which of the following results I prefer:$$Bcm95 Prisoner Count
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . 5 . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . . X X X . . . . . . . X O O O X . . |
$$ | . 4 . O . . . . . . . O O X X O O . . |
$$ | . . O . . X . . . . . . . O X O X O . |
$$ | . O O . 1 . . . . . . . . O X X X X . |
$$ | 2 X O X . . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . 3 . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$Bcm95 Prisoner Count
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . 5 . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . . X X X . . . . . . . X O O O X . . |
$$ | . 4 . O . . . . . . . O O X X O O . . |
$$ | . . O . . X . . . . . . . O X O X O . |
$$ | . O O . 1 . . . . . . . . O X X X X . |
$$ | 2 X O X . . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . 3 . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
or$$Bcm95 Prisoner Count
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . 3 . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . . X X X . . . . . . . X O O O X . . |
$$ | . . . O . . . . . . . O O X X O O . . |
$$ | . . O . . X . . . . . . . O X O X O . |
$$ | . O O . 2 . . . . . . . . O X X X X . |
$$ | 1 X O X . . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$Bcm95 Prisoner Count
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . 3 . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . . X X X . . . . . . . X O O O X . . |
$$ | . . . O . . . . . . . O O X X O O . . |
$$ | . . O . . X . . . . . . . O X O X O . |
$$ | . O O . 2 . . . . . . . . O X X X X . |
$$ | 1 X O X . . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
There's no question that in the latter, which I've now played, I have more points. But in the former, which I came very close to playing, white's groups are cut apart, so I could hope in the longer term to be able to put more pressure on his F2 group this way. In other words, it would be a sacrifice of certain short-term gain for a possibly greater long term one. I decided in the end to just take the instant cash though, as I wouldn't be that confident of making all that many gains in the other scenario, and it also gives black virtually no more sente moves (or ko threats) against the corner, when there would have been several in the other scenario. Plus, if I'm taking sente into the next phase of the game, I start to feel ahead for the first time for a long while in this game, so keeping things simple and grabbing points seems the best option
Note that the situation is a little more complex than robinz's reading indicates. If Black chooses the E6 cut now, it is not "necessarily" sente. The earlier marked kikashi allows White to live against Black's direct attempt to kill. After 1-10 below the marked stone is perfectly placed to give White a snapback...
However, White barely survives. As a result, Black may be able to force White to live in another way that helps Black invade the lower side later, e.g. start with the hanging connection at "a". It would all depend on the evaluation of the alternatives if White plays away here.
$$Bc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . . . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . 5 X X X . . . . . . . X O O O X . . |
$$ | . 1 4 W 7 . . . . . . O O X X O O . . |
$$ | 2 3 O . 6 X . . . . . . . O X O X O . |
$$ | . O O 9 X 0 a . . . . . . O X X X X . |
$$ | O . O X 8 . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . . . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . 5 X X X . . . . . . . X O O O X . . |
$$ | . 1 4 W 7 . . . . . . O O X X O O . . |
$$ | 2 3 O . 6 X . . . . . . . O X O X O . |
$$ | . O O 9 X 0 a . . . . . . O X X X X . |
$$ | O . O X 8 . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$Bc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O X . . . . . . . O . O O O . |
$$ | . . . O . X . . . X . . . . X X X O . |
$$ | . . . . . . . . . . . . X . . . X X . |
$$ | . . O . O . . . . . . . . . . . O . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X O O O O . . . . . . . . . . . . |
$$ | . O X X . X X X . . . . . . . X . . . |
$$ | . . X , X . . . . , O . X . . , X . . |
$$ | . 5 X X X . . . . . . . X O O O X . . |
$$ | . 1 4 W 7 . . . . . . O O X X O O . . |
$$ | 2 3 O . 6 X . . . . . . . O X O X O . |
$$ | . O O 9 X 0 a . . . . . . O X X X X . |
$$ | O . O X 8 . . . . . . . O X . . . . . |
$$ | O O X O O O . . . , . . . . . X . . . |
$$ | X X X O X O . . . . O . . O . . X . . |
$$ | . . . X X O . . . . . . . . . O . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
However, White barely survives. As a result, Black may be able to force White to live in another way that helps Black invade the lower side later, e.g. start with the hanging connection at "a". It would all depend on the evaluation of the alternatives if White plays away here.

:
, B has all these false eyes and later,
is sente:
; B would reduce W's libs with
:
at (a), snapback