After the 4-4 player has made the knight enclosure, bots and post-AI humans have a noticeable difference from pre-AI huamns in the likely follow ups for the opponent (at least this is my impression from watching pro/AI games, I've not done a historical pattern search). The knight's enclosure has been pretty common in top pro play since at least the 90s with Korean style. If white played next in the area it was common to play one of the 2nd line approaches at
a/b, the thinking being (afaik) if you played the regular knight approach when black had already backed off then they could kick and pincer and that was generally bad for you. However, bots will often approach at 2 below anyway, apparently not fearing the kick and pincer. Black will quite often tenuki anyway, and it reverts to white approaching first,
but black got to choose which direction white approach from so could presumably make it the bad one. So why doesn't white fear the kick? From playing around with Lizzie I think the reasons can be
1) white won't extend but tenuki or maybe play the (formerly) "crude" 2nd line hane and atari on top then tenuki
2) white will extend because that's locally a bad shape for black (bad aji at 3-3 and the 2 stones aren't under as much pressure as if black had kicked first and then played the one point jump on 4th line instead of knight to 3rd line -- all stuff we already knew before AI, but I think bots have changed the balance of judgement of these factors) and then if black pincers could
a) tenuki and treat 2 stones lightly for now, not easy to kill aji-free in one move
b) or answer and keep fighting, 2 space jump is a nice haengma for example aiming at corner shenanigans.
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- Click Here To Show Diagram Code
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