The diagram below

is a commonly-identified (local) mistake. Of course, as with many such moves, there must be special cases for it. The position below is from a game between Yi Se-tol (Lee Sedol) and Ch'oe Ch'eol-han (both 9p). The position looks pretty normal, so I'm having trouble finding the reason for

. I assume it has something to do with attacking H3, which would (and did) lead to a running fight (after white responded at C3, black pincered at K3). Moreover, in my database (GoGoD, SmartGo, and some individual games I've added),

is the second most commonly played move in this joseki, albeit a distant second (nearly 600 for J4, and 109 for D2). Anyone have any insight into when this it is better than J4? Is it just when black wants to develop long the bottom or lower-right?
$$Wc
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- Click Here To Show Diagram Code
[go]$$Wc
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