Jiang and Rui, in their three volume text,
The World's New Joseki, point out that traditional 4-4 joseki were mainly used in handicap games, and therefore are often not equitable in even games. Modern pros are discovering/devising new 4-4 joseki, which often involve sharp fighting. And, OC, since the advent of AlphaGo, even more new 4-4 joseki are being played.
$$W Attach and block joseki
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[go]$$W Attach and block joseki
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This attach and block joseki is one of the traditional joseki. Since Black makes an empty triangle, it may be inferior for Black. OTOH, White has two cutting points to worry about.
Has AlphaGo ever played this joseki? Not that I recall. But AlphaGo likes to jump into the 3-3.
Looking at this position afresh, I thought, why not tenuki? And indeed, according to Waltheri (
http://ps.waltheri.net ) the winning percentage for a tenuki is up there with the most frequent plays.
When I was learning go the usual continuation was for White to connect at one of the cutting points and then for Black to cut at the other. I nearly always made the solid connection on the fifth line, and indeed, it is the most popular continuation on Waltheri. Nowadays the solid connection on the third line has fallen out of favor.
$$W Most frequent joseki
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[go]$$W Most frequent joseki
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$$ | . . . , . . . . . , . .[/go]

looks a bit peculiar. How come? Because Black could have made it straightaway.
$$W One space reply
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[go]$$W One space reply
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$$W One space reply
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[go]$$W One space reply
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Does Black really gain anything by exchanging the

stones for the

stones? On an empty board, I don't think so. The bad shape is a big clue.

Black should only play this way, I think, when she believes that White's influence is less than usual.