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Shape problems
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Author:  Bill Spight [ Sun Jun 24, 2012 8:08 am ]
Post subject:  Shape problems

A thread for shape problems. :)

Problem #1:

Click Here To Show Diagram Code
[go]$$Bc Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . X . . X . . . . . . X . . |
$$ | . . . , . . . . . , . . . X . X . O . |
$$ | . . . O . . O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . , . . . . . X . . . . . , . . . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . X . O . . . . . . . |
$$ | . . . . . . . O . . . . . . . O . . . |
$$ | . . . O . . . . . X . O . . . . . . . |
$$ | . . . . . . . X . . . . . . O . . . . |
$$ | . . . O . . . . . O O . . W . , X . . |
$$ | . . . . O X . . X X . . X . X . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


How does Black respond to :wc: ?

Enjoy! :)

Author:  Uberdude [ Sun Jun 24, 2012 8:29 am ]
Post subject:  Re: Shape problems

m2.

First instinct (even an idiot...) was o3 but m2 also means white l3 no longer cuts the black groups which seems to be worth a lot more than the downsides of not playing o3 (1 point less, doesn't take a liberty from o4, white p4 becomes sente but it's not a very useful move).

Author:  lightvector [ Sun Jun 24, 2012 9:43 am ]
Post subject:  Re: Shape problems

Like Uberdude, my first feeling was O3 and then M2 for connecting black's groups. But if M2, and later white's center group gets strong enough, I wonder if is there any lingering aji from something like this?

Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . X . . X . . . . . . X . . |
$$ | . . . , . . . . . , . . . X . X . O . |
$$ | . . . O . . O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . , . . . . . X . . . . . , . . . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . X . O . . . . . . . |
$$ | . . . . . . . O . . . . . . . O . . . |
$$ | . . . O . . . . . X . O . . . . . . . |
$$ | . . . . . . . X . . . . . . O . . . . |
$$ | . . . O . . . . . O O . . O . 2 X . . |
$$ | . . . . O X . . X X . . X 4 X 1 5 . . |
$$ | . . . . . X . . . . . B . . 3 . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . X . . X . . . . . . X . . |
$$ | . . . , . . . . . , . . . X . X . O . |
$$ | . . . O . . O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . , . . . . . X . . . . . , . . . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . X . O . . . . . . . |
$$ | . . . . . . . O . . . . . . . O . . . |
$$ | . . . O . . . . . X . O . . . . . . . |
$$ | . . . . . . . X . . . . . . O . . . . |
$$ | . . . O . . . . . O O . . O 5 2 X . . |
$$ | . . . . O X . . X X . . X 6 X 1 7 . . |
$$ | . . . . . X . . . . . B . 4 3 . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Author:  Bonobo [ Sun Jun 24, 2012 9:48 am ]
Post subject:  Re: Shape problems

I’m a mere 12-14k, but neverthelss …
my first idea was to try an attack from behind resp. within with o7, perhaps o6
and thus could well be that I earn an ashaming defeat, as so often :-! And no, I didn’t play it out.

Author:  illluck [ Sun Jun 24, 2012 9:57 am ]
Post subject:  Re: Shape problems

I can't make up my mind between M2 and N2 XD Both seem to work? I guess M2 leaves a bit less aji on the left side.

Author:  Uberdude [ Sun Jun 24, 2012 9:57 am ]
Post subject:  Re: Shape problems

@lightvector:
Nice idea to look at that aji in the corner, but I think those possibilities are unlikely to arise as white's weak centre group might play forcing moves on the outside around q4/r5 in order to cut off black's r9 stones. And if white doesn't play around there black may well s7 or something pretty soon anyway.

Author:  The Pilgrim [ Sun Jun 24, 2012 12:36 pm ]
Post subject:  Re: Shape problems

Without too much thinking I would play N2 :mrgreen:
With thinking... :scratch: :scratch: :scratch:
I'll think about it tomorrow :D

Author:  Ellyster [ Sun Jun 24, 2012 3:15 pm ]
Post subject:  Re: Shape problems

I would say M4... and connect while attack, but I haven't think it harder

Author:  cyclops [ Sun Jun 24, 2012 5:50 pm ]
Post subject:  Re: Shape problems

q5 why?

Author:  Uberdude [ Sun Jun 24, 2012 6:16 pm ]
Post subject:  Re: Shape problems

@illluck:
I don't see any way in which n2 is better than m2, only worse. If there are only cons, and no pros, why is it a hard choice? Or do I miss a pro?

Author:  illluck [ Sun Jun 24, 2012 6:28 pm ]
Post subject:  Re: Shape problems

@Uber:

I didn't realize that aji until I almost finished posting, and didn't bother to change what I wrote before XD

Author:  Toge [ Sun Jun 24, 2012 11:44 pm ]
Post subject:  Re: Shape problems


Author:  EdLee [ Mon Jun 25, 2012 12:20 am ]
Post subject: 

Bonobo,
Bonobo wrote:
I didn’t play it out.
If this shape is not immediately obvious to you,
then the first thing for you to study is to read what happens if W pushes at o3.
This is the start of the whole discussion. If later, you can find some nice counter-attack for B, great.
But first, what happens if B tenuki and W pushes at o3? Did you even think about this?

Author:  Bonobo [ Mon Jun 25, 2012 6:36 am ]
Post subject:  Re: Shape problems

Thanks, Ed, this again shows that I have a loooong way to go.

My reflexes/instincts/intuition is far from being well-trained, so I’ll keep on following my self-prescription of “play & read & tsumego”, and guess I should stay out of such threads (i.e. not post) unless I’ve at least played around a bit w/ the constellation in question.

Author:  Bill Spight [ Mon Jun 25, 2012 8:45 am ]
Post subject:  Re: Shape problems

The answer:

Click Here To Show Diagram Code
[go]$$Bc Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . X . . X . . . . . . X . . |
$$ | . . . , . . . . . , . . . X . X . O . |
$$ | . . . O . . O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . , . . . . . X . . . . . , . . . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . X . O . . . . . . . |
$$ | . . . . . . . O . . . . . . . O . . . |
$$ | . . . O . . . . . X . O . . . . . . . |
$$ | . . . . . . . X . . . . . . O . 4 . . |
$$ | . . . O . . . . . O O . . W . 2 X 5 . |
$$ | . . . . O X . . X X . . X . X 3 . . . |
$$ | . . . . . X . . . . . 1 . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


:b1: protects against the push and cut and connects to the Black stones on the left.


The game:


Author:  Uberdude [ Mon Jun 25, 2012 12:10 pm ]
Post subject:  Re: Shape problems

I was surprised how old the game was, that Chinese opening shape on the left and top is quite modern, though it did arise in a different order. I liked how Go attacked r9 with his weak reduction group and was particularly impressed how he made such a huge left side with just a few thin stones. I think this is the sort of thing Guo Juan refers to when she says Go Seigen overplays a bit: it doesn't seem fair that he got so much but then maybe my feeling of what is a fair result is wrong. If Sakata couldn't find a way to break it then there aren't many who could. Go Seigen really does show you how to use stones to their utmost efficiency!

P.S.
Uberdude wrote:
@lightvector:
...white's weak centre group might play forcing moves on the outside around q4/r5 in order to cut off black's r9 stones.

:D

Author:  Numsgil [ Mon Jun 25, 2012 1:52 pm ]
Post subject:  Re: Shape problems

Rather offtopic, but I find black's play in that game really slow, at least in the opening. Is it just because the komi was different enough 60 years ago that black doesn't mind playing conservatively? For instance, 7 I'd put one stone to the left to encourage white to play the wedge and decimate the top. White's invested more than black for that to be a big area. My main issue with 7 is that the follow up move, 13, puts black in a low position. He's prevented white's development but he's not building on a large scale himself.

17 especially feels really slow. His entire bottom is flat. White's building some impressive structures and black is building small (but stable) groups everywhere that have an awkward time coordinating in a meaningful way.

I realize these are probably more stylistic decisions than hard and fast rules, but I'm curious of other peoples' thoughts. By 20 I'd greatly prefer playing white, even with my normally more territory oriented play style.

Author:  Bill Spight [ Mon Jun 25, 2012 2:38 pm ]
Post subject:  Re: Shape problems

A few comments on the opening:

:b7: is normal, maybe best.

When I was learning to play, :b13: was one of those moves that showed up in problems, as a big play that is larger than it looks. I never quite bought the argument, but I have made such plays myself. Perhaps pro opinion has changed, I don't know.

:w14: The Chinese-style relationship is not all that new. I have even seen the mini-Chinese in a book (not just a game) from the early 19th century, which indicates that it was not uncommon then. (In handicap play, OC. ;)) This play in particular may show the influence of Segoe on Go Seigen. It is closer to making territory in the top left than a stone under the star point would be.

:b17: was normal, but Numsgil may be right that a higher play would be better.

:w18: allows Black to make a double wing with :b19:. As a play on the frontier of frameworks, it is big. It may show the influence of Dosaku, who performed magic with such plays. :)

:w26: A very Go Seigen move. :) His reduction of the bottom right quadrant is marvelous.

After :w54: as Black I would be worried. But may "Shinogi no Sakata" felt just fine. ;)

Author:  Uberdude [ Mon Jun 25, 2012 3:37 pm ]
Post subject:  Re: Shape problems

Bill Spight wrote:
:w26: A very Go Seigen move. :) His reduction of the bottom right quadrant is marvelous.


Yes, talk about having one's cake and eating it too!

Author:  Bill Spight [ Mon Jun 25, 2012 5:29 pm ]
Post subject:  Re: Shape problems

Problem #2.

Click Here To Show Diagram Code
[go]$$Bc Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . X . . . . . O . . . |
$$ | . . . , . . . . O , . . . . . , . . . |
$$ | . . . X . . . . . . . . . . . . O . . |
$$ | . . . . . X . X W . . . . . . . . . . |
$$ | . . . X . O X . . . . . . . . . . . . |
$$ | . . X O . O X . O O . . . . . . . . . |
$$ | . . . O X O X . O X . X . . . . . . . |
$$ | . . O O O X X O O X . . . . . , . . . |
$$ | . . . O X X O O X O . . . . . . . . . |
$$ | . . O X X O O X X O . . . . . O . . . |
$$ | . . O X O O X X . . . . . . . . . . . |
$$ | . O X X O X O X . . . . . . . X . . . |
$$ | O O O O X X . . . . . . . X . . X . . |
$$ | . O X X X . . . . , . . . . . , O . . |
$$ | . X . . . . . . . . . . O . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


:wc: is the last play.

Enjoy! :)

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