BQM 444

    Keywords: Question

Is this useful ?

Table of contents Table of diagrams
Theme Diagram
Theme Diagram
Options for black
No extension, hane immediately
Extend once then hane, atari (a)
Extend once then hane, atari (b)
Extend once then hane, atari (c)
Extend twice then hane, extend
Theme Diagram

There are a variety positions in which the underneath contact play is useful. Among them is using this play to prevent White from obtaining extra benefit from the unusual knight's move below:

(Note: I can find no record of any professional ever playing black+circle --Herman)

Bill: O Meien (B) - Oba Jyunya, 2006 (Herman: Yes, but this starts from a different shimari)

[Diagram]
Theme Diagram  

Theme

[Diagram]
Theme Diagram  

Starting from black+circle, a possible White response, is the hane of W1 putting the most pressure on Black. Following the sequence to B10, Black is alive. This raises the questions:

  • Can White hane from the third line down to the second and prevent Black from living?
  • Should White hane, what steps should Black take to achieve a better result than that shown in this diagram?

Herman: The end result, after W11 at a, is a horrible disaster for black. There is no way this result is ever acceptable in a game where the space on the left is this open (ie, with no stones from the shimari until the left hoshi). As such, I think that any attempt by white to get an even better result by trying to kill black is an overplay. White gets an extremely good result this way, trying for more can only lead to disaster. Black however, can perhaps improve upon this result by either cutting immediately with B2, or by playing hane on the other side first. Black will certainly get a better result by playing black+circle one line lower at B4

The unusual shimari above straddles the left hoshi. Should the above read upper right hoshi ?

Herman Sorry, I meant the left side hoshi, near the lower edge of the diagram.

[Diagram]
Options for black  

Herman: B6 in the theme diagram is very submissive, by the way. Black should explore options like this combination of B6 and B8.


White immediate hane

[Diagram]
No extension, hane immediately  

The immediate hane of W1 fails. Black cuts at B2 and captures one of the two White stones white+circle or W4


White extends once, then hanes

[Diagram]
Extend once then hane, atari (a)  

Should White extend once then hane. Black crosscuts. Several variations result based upon Whites response.

[Diagram]
Extend once then hane, atari (b)  
[Diagram]
Extend once then hane, atari (c)  

White extends twice, then hanes

[Diagram]
Extend twice then hane, extend  

to be expanded


White extends thrice, then hanes

to be added


Bob McGuigan: Isn't the unusual white "shimari" usually played for outside influence? The variation in the theme diagram gives White just what she wants while Black crawls on the second line and ends in gote. Timing of the attachment seems to be important. Furthermore there are other ways for Black to limit White's corner territory, including a direct invasion at several points, though any invasion will give White outside influence and likely end in gote for Black. In the theme diagram variation reproduced below White can play at white+square in sente, too, adding thickness.

hhw: I suppose the point is that thickness would not be too helpful for White. Since Black was willing to attach black+circle on the second line.

Velobici: Agreed, the unusual white "shimari" is played for outside influence. If there is a strong Black position in the facing corner, White's choice is rather queer. Black needs to know how to handle the attachment in the theme diagram on this page, as well as, how to handle the other ways for Black to limit White's corner territory, including a direct invasion at several points. Each of these would be a valuable page. Creating a page on the unusual white "shimari" that references each of these pages (this attachment and the direct invasions) would be even better. Would you be interested in working on one of those pages ?

Tapir: See 3554Enclosure (I'm interested btw but pretty incompetent). In the line given i wonder whether "I suppose the point is that thickness would not be too helpful for White." can be true under any circumstances.

[Diagram]
Theme Diagram  

BQM 444 last edited by Dieter on October 25, 2009 - 12:59
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