A position analogous to this appeared in one of my games recently.

Click Here To Show Diagram Code

[go]$$B Capture to force a play inside?
$$ --------------
$$ | . . . O . . .
$$ | . X X O . . .
$$ | O O O X O O O
$$ | O c O X b . .
$$ | X X O X O . .
$$ | . a X O O O O
$$ | . . X X X X X
$$ | . . . . . . .[/go]

If white wants to force black to connect at a (filling in a point of territory), she needs to capture at b before filling the dame point c. Likewise, black could atari, to force a capture at b, but would then need to connect at a afterwards.

Or, both players could be apathetic and just let the situation be at the end of the game. I suppose it's moot for scoring purposes, so it's a net zero points, and therefore not worth playing by either player, but are a and b territory then? Again, it's moot because it's net zero points, but are they technically required to play? (e.g. during the dame-filling stage in Japanese rules)

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KGS 4 kyu - Game Archive - Keyboard Otaku

Area scoring: A player wishing to get C needs to play before scoring.

Territory scoring: It depends on the ruleset. In particular J1989 / J2003: C is a dame so that either adjacent "group" is in-seki and there is no territory on the board yet. Verbal Japanese Rules are more liberal.

It's Teire Dame I think.

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Laurens
Go school: freegame's Teaching School
Author of: The Next Move a book for 15-3kyu players.

Thanks, that makes sense.

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KGS 4 kyu - Game Archive - Keyboard Otaku

Click Here To Show Diagram Code

[go]$$B Startposition
$$ --------------
$$ | . . . O . . .
$$ | . X X O . . .
$$ | O O O X O O O
$$ | O c O X b . .
$$ | X X O X O . .
$$ | . a X O O O O
$$ | . . X X X X X
$$ | . . . . . . .[/go]

I like the Ikeda area III rules http://senseis.xmp.net/?IkedasRule
and here is my analyse of the position using these rules.

All have the startingpoint that there have been no passes before. (under these rules white get a point more if he passes first, but in a rather complex way, i keep here to the original description)
I don't claim to be an expert here so please comment than we can all learn together

I think the main playouts to concider are:

1a) - Black to move Bpass - Wb- Bpass-Wc- Ba

result (after removing dead stones)

Click Here To Show Diagram Code

[go]$$B Endposition 1a
$$ --------------
$$ | w w w O w w w
$$ | w w w O w w w
$$ | O O O w O O O
$$ | O 4 O w 2 w w
$$ | X X O w O w w
$$ | b 5 X O O O O
$$ | b b X X X X X
$$ | b b b b b b b[/go]

so white 37 area
black 19 area
Difference 18 to white

1b) - Black to move -Ba - Wb- Bpass-Wc

result (after removing dead stones)

Click Here To Show Diagram Code

[go]$$B Endposition 1b
$$ --------------
$$ | w w w O w w w
$$ | w w w O w w w
$$ | O O O w O O O
$$ | O 4 O w 2 w w
$$ | X X O w O w w
$$ | b 1 X O O O O
$$ | b b X X X X X
$$ | b b b b b b b[/go]

white 37 area
black 19 area
difference 18 to white

1c) - Black to move Ba - Wb- Bc-Wpass

result (after removing dead stones)

Click Here To Show Diagram Code

[go]$$B Endposition 1c
$$ --------------
$$ | w w w O w w w
$$ | w w w O w w w
$$ | O O O w O O O
$$ | O 3 O w 2 w w
$$ | X X O w O w w
$$ | b 1 X O O O O
$$ | b b X X X X X
$$ | b b b b b b b[/go]

white 36 area + 1/2 point for white passing first
black 20 area - 1/2 point for white passing first

so white 36 1/2 point
black 19 1/2 point
difference 17 to white

2a) - White to move Wb- Bpass-Wc- Ba

result (after removing dead stones)

Click Here To Show Diagram Code

[go]$$W Endposition 2a
$$ --------------
$$ | w w w O w w w
$$ | w w w O w w w
$$ | O O O w O O O
$$ | O 3 O w 1 w w
$$ | X X O w O w w
$$ | b 4 X O O O O
$$ | b b X X X X X
$$ | b b b b b b b[/go]

white 36 area + 1/2 point for white passing first
black 20 area - 1/2 point for white passing first

so white 36 1/2 point
black 19 1/2 point
difference 17 to white

2b) - White to move Wpass- Ba-Wb- Bc

result (after removing dead stones)

Click Here To Show Diagram Code

[go]$$W Endposition 2b
$$ --------------
$$ | w w w O w w w
$$ | w w w O w w w
$$ | O O O w O O O
$$ | O 4 O w 3 w w
$$ | X X O w O w w
$$ | b 2 X O O O O
$$ | b b X X X X X
$$ | b b b b b b b[/go]

white 36 area + 1/2 point for white passing first
black 20 area - 1/2 point for white passing first

so white 36 1/2 point
black 19 1/2 point
difference 17 to white


So taking these all for black best is to play Ba followed by Bc
And for white passing or capturing makes no difference.
but do maybe i made a mistake

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Promotor and Librarian of Sensei's Library