Kyus at work  

tapir: this is from recent blitz games of mine. since my opponent consistently played this opening (i m black). i tried to convince him by game play that this opening is not good for white. however, odds were 2:3 at last (that is he won despite this opening). so i long for, other convincing arguments in form of tewari or anything else. thank you.

Kyus at work II  

Andy Pierce: I don't like since it makes inefficient. If black is going to play , then he would much prefer at a. White had to patch up with , which is why this joseki is isn't so good for black without a stone on the left already in place (see: 44PointOneSpaceLowPincerInvasionBlock). Since black gets a free move while white patches with , I think black should immediately counter-pincer while extending from the hoshi stone in the upper right in this manner^[100].

tapir: The in the top right looks odd imho after white fixes up the joseki. If anything I would like to have an approach in the lower left then. at a may be better now, but leaving white splitted looks so good to me, I didn't need time to think about at all. (It was blitz anyway.)

Bill: I don't particularly like , either. I prefer b, as Black is alive in the corner. It is not like White can afford to cut with gote. ;)

Kyus at work III  

Tewari

Tewari at work  

Herman: Suppose white chooses to ignore the approach , and play a counter-approach , making the upper corners miai. is reasonable, supporting while pincering . White enters the corner.

Tapir: Thanks! Very convincing, I try to live up to this by winning next time. :) Btw. how do you answer such symmetrical plays like here. I usually would play the starpoint 10-4 or 10-3, but maybe this is unnecessary shy.

Herman: Pincers like 10-4, 10-3 or in the diagram are all good moves, because they also support and are thus dual purpose moves. Black can also choose to simple extend and play one of the 4-4 point low approach, low extension joseki. If this ends with white pincering , which it could, is not in trouble because white has not responded on the left. So black can counter-pincer or enter the corner and should be fine. Personally, I would have slight preference for one of the pincers, but an extension cannot really be said to be wrong.

Tewari at work II  

Herman: After white takes the upper right corner, black decides to take the upper left with . White builds a wall to influence the left and work with

Tewari at work III  

Herman: defends against the double cut on the second line, stakes out the left. is a good move, expanding blacks top moyo while reducing that of white on left. is a very bad move. It is far too close to black's strong stones in the upper left. It is pre-pincered by , so doesn't have any potential to make a base on the top. is the natural response, pressing down on white's moyo on the left while attacking

Kyus at work again  

Herman: White can now play at a, and I think then becomes slack, and does not punish white effectively, because of the following tewari....

Tewari at work again II  

Herman: Up to is joseki in the upper left, but this is usually bad for white is there is no stone at or around . With , black is playing on the unimportant side ( and do not make much influence here), allowing white to patch up his defect with . Instead, black should have invaded the left side (at a, for example) to make white's wall ineffective or overconcentrated.

Andy Pierce: Well that seems simple enough. Not to get all tewari or anything, but since white should have had a stone around a already before initiating the joseki, black can mess white up by putting his stone down where white's stone should have been.

No GoBase pro games  

There are no games on GoBase in which White blocks at .

The pro move  

There are at more than 100 games on GoBase in which White plays here.

I think a simple answer is that playing on the "wrong" side as White does in the game diagram and playing the left side star point before finishing the joseki in the upper left is inconsistent. White doesn't get a good moyo on the left side and really isn't using the pincer stone fully on the upper side. White's three stone wall in the upper left corner is heavy, not thick, when the joseki isn't finished.