I’ve had this position on my mind lately, ever since @Samraku sprang it on me.
I first checked OJE, which merely calls it a “fighting pattern”. Then I asked Clossius, who pretty much just told me to look it up on Josekipedia. So I looked it up on Josekipedia to discover that the variations there were the same as on Waltheri. With that in mind, I explored the context on Waltheri but the positions were almost all from the midgame.
What is White to play here?
You can obviously take the corner, but it feels a bit sad:
You could also make the ladder sacrifice (which is what I played in the game), but that doesn’t work all that well against this particular pincer spacing:
White could simply cover and jump out:
Or he could shoulderhit, although this is a bit suspect as the cut is valid:
The obvious thing you notice is that, compared to (3) P18+, the top-side endgame in Kata’s variation is worse but the right-side endgame is better, and there is also more aji left for White around Q14.
I don’t feel that this is much better than (3) P18+, but there does seem to be a subtle improvement.
I prefer huge network and little playouts.
I think when there are too many playouts, it may start to choose variations that are best in current full board position instead of variations that are usually good. And current full board position is strange: empty.