I believe the slide is more common when black has a low stone because white is trying to make black feel a bit cramped, whereas sliding when black has a high stone helps black settle his position easier. For this same reason, when black has already played low and white slides, black prefers to play the diagonal move at , let white into the corner, and then extend along the side.

Click Here To Show Diagram Code

[go]$$B
$$ --------------------+
$$ . . . . . . . . . . . . . |
$$ . . . . . . . . . O . . . |
$$ . X . O . X . O . . 2 . . |
$$ . . . , 1 . . . . X . . . |
$$ . . . . . . . O . . . . . |
$$ . . . . . . . . . . X . . |
$$ . . . . . . . . . . . . . |
$$ . . . . . . . . . . . . . |
$$ . . . . . . . . . . 3 . . |
$$ . . . . . . . . . , . . . |[/go]

(if you're really interested in this pattern, see http://www.koreatimes.co.kr/www/news/art/2010/08/152_18262.html and http://www.koreatimes.co.kr/www/news/art/2010/08/152_18918.html)

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Each of us woke up one moment and here we were in the darkness.
We're nameless things with no memory; no knowledge of what went before,
No understanding of what is now, no knowledge of what will be.

Yeah, I think my website should process this position a little differently.

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How do you define the pattern area? I haven't used your site much, so it's not clear to me.

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Perhaps, but I'm not sure if you are missing my point or not. The purpose was to illustrate that looking for severe punishments is probably not possible, because the shape is so close to usefully playable in general terms that it can't be that outright bad. The fact that, with different local stones, the slide is effectively kikashi and fine, means that in the worst case it is surely likely to be non-severe aji keshi?

It would be interesting to see the amount of professional games where the slide got played and where the 3-3 invasion got played (and where neither got played) to see how much aji is actually being keshied (sorry John!).

Short answer: I have an algorithm (if I explained it, this wouldn't be a short answer!) that tries to be intelligent about the pattern size. It is not optimal (I believe that it handles invasion sequences poorly, for example), but it seems to work quite well most of the time. Since making it I've realized that there's (probably) an objectively correct way to do this, but I haven't had time to investigate it.

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That which can be destroyed by the truth should be.
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@mw42

I'm not saying the large knight's move is bad. I'm just responding to you saying the small knight's move is bad, which is incorrect. It is a common joseki which pros play frequently as stated by me, topaz, etc.

As for the slide, in handicap games (where I'm white), and often in even games I play it all the time because I don't want to give my opponent the option of kicking. Especially when I don't care about the corner I think it's a useful move. I hardly think it's fair to classify it as aji-keshi.

I'd love to see an example in a pro game, cloud.

Here is a link from Daily Joseki. Small knight's move:

http://dailyjoseki.com/browse/bwpwxibxgwvsbvawyfbxl

This position was reached 229 times.

Your move (Large knight's move):

http://dailyjoseki.com/browse/bwpwxibxgwvsbufwyfbxl

This position was reached 20 times.

Cloud, I don't mean to sound rude, but did you read my posts? My whole argument for the large knight's move being superior to the knight's move is based on the exchange before .

I don't understand your argument. Just because the order changes doesn't mean that the result you would get after making the small knight's move is no longer joseki. There is no reason to reject the move just because the slide occurred first.

I can perhaps explain - a reason I've often been told why we should play the small knight's move, not the large knight's is that the 3-3 invasion under the large knight's is better. So if black has already forfeited his ability to play the 3-3, the large knight's move gains ground as a choice.

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Yes, this is why the ogeima isn't usually played if white jumps out first. However, if white slides first than the ogeima becomes the proper extension from a two stone wall.

@mw42: Regarding the long knight, I'd be slightly cautious about the following aji at 'a' - The security of the short knight would be worth eliminating that aji IMO:

Click Here To Show Diagram Code

[go]$$Bc
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . . 4 . . . |
$$ . . 3 . 2 . . 5 . . |
$$ , . . . . . 1 . . . |
$$ . . . . 6 . . a . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 7 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 8 . . |
$$ , . . . . . , . . . |[/go]

Click Here To Show Diagram Code

[go]$$Bc
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . . 4 . . . |
$$ . . 3 . 2 . . 5 . . |
$$ , . . . . . 1 . . . |
$$ . . . . 6 . . . . . |
$$ . . . . . . . 7 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 8 . . |
$$ . . . . . . . . . . |
$$ , . . . . . , . . . |[/go]

Even with a keima I'd want to respond here.

By the way, just to clarify, I never said the keima would be bad in the situation just sub-optimal. Just as playing a two-space extension from a two stone wall would be sub-optimal, but it is still the correct play at times.

Sure, but with the short knight, Black can fix happily with points:

Click Here To Show Diagram Code

[go]$$Bc
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . . 4 9 . . |
$$ . . 3 . 2 . . 5 . . |
$$ , . . . . . 1 . . . |
$$ . . . . 6 . . . . . |
$$ . . . . . . . 7 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 8 . . |
$$ . . . . . . . . . . |
$$ , . . . . . , . . . |[/go]

with the long, he can't fix so easily, as this move still has a lot of aji:

Click Here To Show Diagram Code

[go]$$Bc
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . . 4 9 . . |
$$ . . 3 . 2 . . 5 . . |
$$ , . . . . . 1 . . . |
$$ . . . . 6 . . 0 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 7 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 8 . . |
$$ , . . . . . , . . . |[/go]

b9 looks bad there; given that 6 and possibly 8 lack a base, something that separates 8 from 6 would be in order?

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Sorry, I wasn't very clear. The illustration was more for later game aji, as opposed to immediate plays. I think is overplay if played immediately.

That's fine. Just something to be aware of if you happen to play that shape. Blocking the corner at is typically big yose anyway, so perhaps in that shape it's even larger. Still, the life of the black group is not in danger with your diagram.

With the short knight, is normal, because of the peep aji if Black doesn't play it. Also, once is played, the aji is completely gone from the whole corner.

With the long knight, there are some very complicated continuations with that last invasion, of which most seem to only almost work, though some I can't read out to my satisfaction - the fact none of those continuations exist with the short knight would have to make me have to really really want those extra 4 points to play long.

It seems to me that after if then white should die.