Looking at all of this analysis, I'm surprised that I have not read the word 'heavy' nor the word 'light'. IMHO, that distinction is the most relevant issue.

Black has a choice between attacking a light stone with 'b' or 'c', or some heavier stones with 'd'. White cannot really ignore 'd' because he has too many moves invested in the corner. He can, however, ignore 'c' because is light.

IMHO, it is a no brainer: black must play 'd'.

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Well, 4 just doesn't look good, pretty sure that's not how we want to follow-up the 1-space low.

Normally though, white would leave the bottom left with sente, This is as though white left the bottom left with sente, and approached black from exactly the wrong direction.

I think if it were me, I'd go with one of the following:

Click Here To Show Diagram Code

[go]$$Wc Variation 2
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . a . . |
$$ | . . . 3 . . . . . . . c . . . . . . . |
$$ | . . O , X X . . . . . . . . . X . . . |
$$ | . . . O O X . . . . . 2 . 1 b . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

the logic being,

"a" makes splitting the right side difficult,
"b" either makes white heavy or makes black so thick that invasion of the lower side is untenable
"c" takes care of the long extension from the lower left, but risks black becoming overconcentrated when white jumps to 3x3. However, if white DOES jump to 3x3, black keeps sente, solidifies his lower side and gets to move to the upper left. So I think it's playable.

I lean toward "a" or "c", b could very easily end up being slow.


The danger to my approach is that the white stone in the bottom right becomes light, and black has lost an opportunity. I will readily admit that, but stabilizing the bottom right and the right side feels so good.

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