BQM 265

    Keywords: MiddleGame, Question

In his ThePowerOfTheStarPoint, Shukaku Takagawa looks at a game between Sugiuchi Masao (white) and Otake Hideo from the 13th Old Meijin league (GoGoD 1974-05-01b). He describes moves 1 and 3 "perfect timing," and "extremely big."

[Diagram]
Fig. 2, page 68  

Is it just all about the aji? Taking gote here seems a pretty high price.

Thanks

Bob McGuigan: I'd say these moves are sente in this situation.

Nick George: Bob, the next move is W4. Is that in response?

Bob: Well I'm no pro. But because the upper left lone black stone can be activated and the left side white area is open at the skirt on the lower left it doesn't look like White can make a lot of territory there. So I would want to answer on the lower side, because of the aji left there. But what do I know?

Bill: In a way W4 is in response to B1 - B3. Without W4 B a is keshi and a ladder breaker for the cut at b.

Thad: I'm sorry. I see how B a breaks the ladder, but I do not see how W4 restores the ladder. Can you show a sequence?

HermanHiddema: W4 does not restore the ladder,[1] but before W4, a is a dual purpose move, breaking the ladder and threatening to play c. W4 removes one of those purposes, so now if B plays a, W can answer at or around b

Nick George: ladder shmadder! A net would work fine.

HermanHiddema: What net? If B plays d, W descends and B cuts, there's a lot of aji. A ladder would certainly solve a lot of that. Breaking the ladder is not the main purpose of W4. It is a good move, expanding the W potential in the centre a lot. The ladder is just a detail.

Nick George: heh heh... nevermind... that kind of reading is what keeps me from reaching single digit kyu.

Bob McGuigan: Thinking about it a bit more I think W4 is almost required. Imagine Black playing in that area. It is a junction of two moyos.

[Diagram]
Fig. 2, page 68  

Jared: Perhaps a black play around a is more forceful now. White responding at b would be sente (threatening the corner) without the B1 - B3 sequence.

zinger: Wow! Can you show the sequence for that?

[Diagram]
Fig. 2, page 68  

unkx80: W1 and W3 makes the invasion at B4 much harder, because W5 is sente. If Black ignores the sente move, W7 kills. Subsequently, a possible variation is Black a to White d.

HermanHiddema: This sequence switches sente (so assumes that black plays tenuki first). I think zingers question was to show a sequence where black invades immediately at B4, white answers W5 and B plays B6. After that, there is no realistic sequence to kill the corner really.

[Diagram]
Fig. 2, page 68  

unkx80: There is also the aji at B1 and B3 (sniff, sniff). Together with moves like a and b, White's territory may not be totally secure.


Notes

[1] RP: What? The ladder broken by black+circle certainly no longer is after W4: after his clamp at d, her descent, and his cut at b, she captures his cutting stone by starting a ladder with two (not three) ataris from the right and one from above.

xela: My interpretation of the discussion is that they weren't talking about the black+circle stone (which doesn't break the ladder in any case, because of the white stone a knight's move below W4, although as you point out, black can still clamp, and W4 indirectly prevents that). Bill's slightly cryptic sentence could be interpreted as: if white omits W4, and if black plays a, then the ladder is broken -- which seems to imply that with both W4 and black a on the board, there is still a ladder. Herman says no, black a breaks the ladder even if there is a stone at W4. I agree with Herman.

Bill: Sorry for being so cryptic so long ago. How could W4 be a ladder maker? for a ladder from the bottom left corner broken by a?


BQM 265 last edited by 107.210.159.110 on January 28, 2020 - 15:44
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
RecentChanges
StartingPoints
About
RandomPage
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Goproblems.com
Login / Prefs
Tools
Sensei's Library