Press lower right, press upper left, then two-space high shimari upper right. Of course, White might disagree…

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[go]$$Wcm8 Yasui Chitetsu (W) vs. Honinbo Dosaku, 1668-10-03a
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Chitetsu left the top right corner and the bottom left corner as miai and played a pincer in the top left corner. That's a reasonable strategy, except that, starting with AlphaGo, today's top bots do not like the early pincer, as a rule. Elf docks this pincer 16½% to par. Dosaku then enclosed the top right corner, another reasonable choice, which Elf docks 13% to par. Elf, along with Harleqin, prefers the press at a in the bottom right instead.

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[go]$$Wcm8 Mainline for
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I don't know about other bots, but for Elf prefers the shoulder hit against , which has the advantage of averting the press at 16. , a, and are possible replies, but Elf slightly prefers the press at in the top left corner. Then Black returns to play in the bottom right. blocks, cuts, and then White pulls back with .

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[go]$$Bcm17 Mainline for , continued
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Black now sacrifices the stones in the corner. For Elf has a slight preference for a, but the solid connection is sound.

The press from the 5-3 against the 3-4 is a real workhorse.

Oh, it's White to play. Then I'd be inclined to play kosumi in the lower right. Actually, I'd want to enter lower left, but then Black presses on both sides and attacks the lone stone on the lower side. So, the kosumi lends some support, prevents the press, keeps the black stone weak(ish) and maybe even makes miai of approaching/entering the lower left and upper right.

Speculatively:
Current position:
1. C3 (or C4) is obvious, but clearly too obvious given the comment.
2. So lower right is the tensest situation. W's AI punishment is at O4 I think. Traditional play is Q3 or Q6.

Opp to play
1. Press on lower right then pincer (or even just shimari lower left) is severe.

Past:
1. W getting extra move in lower right probably means W marginally gains.

Check:
1. seen before