Fllecha wrote:Until white 22 it's joseki, but now black insead of extending the wall, he easily steals white's big corner. In the end he will not get wall+extension but if white invade in the triangled final zone black can still attack her. Why nobody plays this way as black? Is white compensation ok? Can you clarify final position?
Starting with the last question first, no, I cannot clarify the final position. Edit: The reason is that I did not look at it. I agree that
was bad. It should have been a hanging connection.
The corner is not big. Why not? Because White is solid on the top side, and White has an extension towards the left side from the corner. Taking the corner can only make territory. That is too limited an objective this early in the game.
Now, it is not true that nobody plays this way as Black. Waltheri (
http://ps.waltheri.net ) shows two games where the corner invasion came immediately, somewhat less than ¼ of the time. (Those games match the top half of the board only.)
Why did two top pros make the 3-3 invasion, if the corner is not big? The reason is that the invasions were probes. In each case the invader forced the defender to choose which side to block on and took sente, leaving aji behind and the corner unsettled.
This is an old fashon joseki that had a revival thanks to AlphaZero. The final position is black sente and white territory: the old evaluation was "Black (with that infuence) is locally better. AG says that position is even, but in any case not worse for black.
Moi, I don't see how the influence makes Black "locally" better. For one thing, influence is not local, and besides that, I like influence and I still don't see that it is better in general than the underneath connection. {shrug}
My question is: how can I use that influence? Or, put it another way: What is black LOCAL direction of play?
I think you can answer the second question yourself.
And get "LOCAL" out of your head. Influence in the opening is not local.
As for the first question, that is perhaps a bit difficult to explain. It is true that a lot of amateurs find it difficult to utilize thickness. The standard answer is to use it to attack, but attacking is not easy. {shrug}
In playing over ancient games from a few centuries ago, I discovered something that may help explain how to handle this kind of thickness. Players of that era were more territorial than players today, but they did not shy away from making influence (thickness) and letting their opponent make territory. One thing that surprised me was how often they did not seem to make use of that thickness. Now, by the time I was studying those games I already knew how to use influence on one part of the board to make territory on another part of the board, or to take away territory elsewhere. But these guys just seemed not to do much with the thickness. They did not use it to make territory, OC, but they did not use it to attack, either. It just sat there.
This looks like the kind of thickness that you can let sit. How come? First, its particular shape is primed to make eyes, so it is fairly robust. Second, White has the large slide one point further than the one Uberdude shows, so building a good framework on the top side is not easy for Black to do. At the same time, White is not going to accomplish much on the top side, either. Given all that, what is there to do? In the immortal words of the Beatles,
Let It Be.
What about the White slide that Uberdude shows? As he points out, that eliminates Black E-18, which would then threaten to make a moyo. It also undercuts the Black thickness, which makes it more difficult for it to live. White may then be able to make hay by attacking Black. But all that is down the road.
). Before learning Joseki it is nice to decide which moves are the best in fuseki, then you only have to deal with a lot less Joseki.)
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