BQM 171

  Difficulty: Advanced   Keywords: Joseki, Tactics, Question

Arno: I am just reading Redmond's "The ABC's of attack and defense". Talking about double approach moves, the following position arises:

[Diagram]
Double approach move  

Redmond next gives the line starting with a and discards playing at b:

[Diagram]
the expected followup  

After making the corner solid with W1 and W3, White turns to W5 and Black makes the thick move of B6, so that White has no more forcing moves from the outside which could help the two white stones. Next the fighting turns to the 4 black stones on the left.

[Diagram]
bad for white  

Redmond says that playing W1 or any other move from the outside is bad, because Black can capture the white+circle stones. This due to the fighting move of black+circle which robs White of the necessary liberty.

But what about the following line?

[Diagram]
outcome?  

No matter how hard I think I come to one of two conclusions:



  1. either Black must endure a forcing move from the outside which he needs not endure in the "followup diagram". Thus White would have gained something.
  2. or Black captures the corner in gote while White captures the two black stone on the outside. That can't be good either. Or is it?

So what to do next?


[Diagram]
Good for Black  

Bill: Isn't this good for Black?

[Diagram]
still trouble in the corner  

Arno: If W1 and B2 tenuki, White can still live in the corner. I don't think that this is good, is it? If it is good, then my assessment (option #2 of my question) is off. But I like to be corrected :-)

The reason I think this is bad is that after W1 if Black invests another move in the corner (W3?) to make sure it is indeed dead White can play somewhere down the left side and has established a foothold there too that nullifies Black's thickness. On the other hand White has nice influence torwards the right.

Bill: After W1 - B2 -- I think B2 works -- the white+circle stones look like mochikomi to me. As for the black+circle stones, Black still has a kikashi at a. In addition, white+square has, in effect, approached strong stones, and is quite weak.


Charles Always try to argue with pro 9 dans about joseki ... not.

[Diagram]
Double approach move - continuation  

Actually, looking at real games, it is B1 here that they play, in the absence of any pincer.

If there is no pincer, then Black should not be getting a very acceptable result here. Modern thinking seems to be that the diagonal move B1 in the first diagram is OK; but I really wouldn't recommend it, as a teacher.

dnerra Without any pincer, Black usually tenukis after the diagonal move and White's 3-3 invasion. This is more flexible, as Black can decide later on which side to block, or just to jump out with a two-space jump from the diagonal move. If one understands that this is mostly about flexibility, then I might think it can well be recommended.

Charles I wouldn't be trying to teach anything to anyone who understands that much about go ...

Bill: I believe that Maeda came up with the idea of kosumi - san-san - tenuki in the '70s.

I couldn't quickly find the standard joseki.

[Diagram]
Time-honoured way  

This is very old joseki. Black takes the corner here, with some aji; White develops on both sides.

With this as reference, I think White's loss in Bill's 'Good for Black' diagram may be clearer.


BQM 171 last edited by CharlesMatthews on July 5, 2004 - 20:28
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