W's best move?

For lessons, as well as threads about specific moves, and anything else worth studying.
Post Reply
User avatar
jts
Oza
Posts: 2662
Joined: Sat Sep 18, 2010 4:17 pm
Rank: kgs 6k
GD Posts: 0
Has thanked: 310 times
Been thanked: 632 times

W's best move?

Post by jts »

Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . . X O X O . . . . . . . . . . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . O O O O . O . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . O . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


If it's W to move, what's the best W can do on the left side?
User avatar
topazg
Tengen
Posts: 4511
Joined: Wed Apr 21, 2010 3:08 am
Rank: Nebulous
GD Posts: 918
KGS: topazg
Location: Chatteris, UK
Has thanked: 1579 times
Been thanked: 650 times
Contact:

Re: W's best move?

Post by topazg »

Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O W . . . . . . . . . X . . . . |
$$ | . . X O C O . . . . . . . . . . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . O O O O . O . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . O . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Probably my choice ...
User avatar
1986
Lives in gote
Posts: 502
Joined: Thu Nov 11, 2010 1:55 am
Rank: malk-5k
GD Posts: 0
KGS: go1986
Location: Coloradao USA
Has thanked: 50 times
Been thanked: 12 times

Re: W's best move?

Post by 1986 »

i second what topazg said without that move W could be in danger, Its simple and sweet :study:
standing still means going backwards
illluck
Lives in sente
Posts: 1223
Joined: Sun Apr 25, 2010 5:07 am
Rank: OGS 2d
GD Posts: 0
KGS: illluck
Tygem: Trickprey
OGS: illluck
Has thanked: 736 times
Been thanked: 239 times

Re: W's best move?

Post by illluck »

The block is sente, so I'd just play that. Then I want to play on the right side. For example, something like below?

Click Here To Show Diagram Code
[go]$$W 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . 1 O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O a . . . . . . . . . X . . . . |
$$ | . . X O X O . . . . . . . . . . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . 3 . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 2 . . . . . . . . . . . . . X X . . |
$$ | . O O O O . O . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . O . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


"a" seems fairly important, but white can push out and separate black if black plays it (or even just tenuki).
DJLLAP
Lives in gote
Posts: 602
Joined: Mon Apr 16, 2012 3:32 pm
Rank: 1 kyu KGS
GD Posts: 0
Universal go server handle: djllap
Location: Denver, CO
Has thanked: 4 times
Been thanked: 47 times

Re: W's best move?

Post by DJLLAP »

Honinbo Shusaku vs Yasui Sanchi (almost)
Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O . W . . . . . . . . X . . . . |
$$ | . . X O X O . . . . . . . . . . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . O O O O . O . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . O . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]




According to Yasui Sanchi under slightly different board position this is better than the capture, though I don't really understand why.
illluck
Lives in sente
Posts: 1223
Joined: Sun Apr 25, 2010 5:07 am
Rank: OGS 2d
GD Posts: 0
KGS: illluck
Tygem: Trickprey
OGS: illluck
Has thanked: 736 times
Been thanked: 239 times

Re: W's best move?

Post by illluck »

DJLLAP wrote:According to Yasui Sanchi under slightly different board position this is better than the capture, though I don't really understand why.



Better influence on the outside. The liberty doesn't matter because white's three stones below has more than enough and the peep isn't worth much for black.
User avatar
topazg
Tengen
Posts: 4511
Joined: Wed Apr 21, 2010 3:08 am
Rank: Nebulous
GD Posts: 918
KGS: topazg
Location: Chatteris, UK
Has thanked: 1579 times
Been thanked: 650 times
Contact:

Re: W's best move?

Post by topazg »

Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . B . . . . |
$$ | . X O O W . . . . . . . . . B . . . . |
$$ | . . X O C O a . . . . . . . . . . . . |
$$ | . . X X O X . . b . . . b . . . . . . |
$$ | . X . O O . . . . , . . . . . , . . . |
$$ | . . . . . . . . b . . . . . . . . . . |
$$ | . . . . . . . . . . . . b . . B X . . |
$$ | . O O O O . O . . b . . . . . B O . . |
$$ | . X X . X . . . . . . b . . . B O . . |
$$ | . . X . X . . . . . . . . . . B O . . |
$$ | . . . , O . . O . , . B . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


The nobi is nice, I like that - but the reason I wouldn't use the block is because I'm also concerned about the influence the marked Black stones have over the "b" area. Moves like "a" are nice to remove from Black's options IMO :) The fact it secures White's group too makes it a useful dual purpose move, as well as being thick.
User avatar
jts
Oza
Posts: 2662
Joined: Sat Sep 18, 2010 4:17 pm
Rank: kgs 6k
GD Posts: 0
Has thanked: 310 times
Been thanked: 632 times

Re: W's best move?

Post by jts »

Spoilers ahead!

This is the Shusaku/Sanchi game, I believe.

Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . . X O X O . . . . . . . . . . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . a O O O . O . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . X . X . 7 . . . . . . . . X O . . |
$$ | . . . , O . 3 O . , . . . . . , O . . |
$$ | . . . X O . 1 2 . . O . . X . X X O . |
$$ | . . . X . 5 4 6 . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


The commentary says that B strengthens his corner with :b1: , etc., because a white stone at A is sente against the left side. But I can't figure out what exactly W can do if B ignores A, or if B defends the corner instead of the side. Thus the question.
User avatar
topazg
Tengen
Posts: 4511
Joined: Wed Apr 21, 2010 3:08 am
Rank: Nebulous
GD Posts: 918
KGS: topazg
Location: Chatteris, UK
Has thanked: 1579 times
Been thanked: 650 times
Contact:

Re: W's best move?

Post by topazg »

Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | 3 . X O X O . . . . . . . . . . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . . . , . . . |
$$ | . 2 . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . O O O O . O . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . O . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]



This is the move I'd been looking at first, it looks alive to me though :S (hence making another suggestion)

Maybe :w2: @ :b3:?
User avatar
Joaz Banbeck
Judan
Posts: 5546
Joined: Sun Dec 06, 2009 11:30 am
Rank: 1D AGA
GD Posts: 1512
Kaya handle: Test
Location: Banbeck Vale
Has thanked: 1080 times
Been thanked: 1434 times

Re: W's best move?

Post by Joaz Banbeck »

Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . . . . . . O O X . . . |
$$ | . X O O 2 4 6 . . . . . . . X . . . . |
$$ | . X O O 1 3 5 . . . . . . . X . . . . |
$$ | . . X O X O . . . . . . . . a . . . . |
$$ | . . X X O X . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . a . a . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . O O O O . O . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . O . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I don't understand the concern about E12. Sure, it is a nuisance, but little more for white has the driving tesuji to get out. And if black tries too hard, he is just playing toothpaste go.

So I tend to like Illuck's suggestion of reducing the right side with something around the point marked 'a'.
Help make L19 more organized. Make an index: https://lifein19x19.com/viewtopic.php?f=14&t=5207
User avatar
topazg
Tengen
Posts: 4511
Joined: Wed Apr 21, 2010 3:08 am
Rank: Nebulous
GD Posts: 918
KGS: topazg
Location: Chatteris, UK
Has thanked: 1579 times
Been thanked: 650 times
Contact:

Re: W's best move?

Post by topazg »

Joaz Banbeck wrote:
Click Here To Show Diagram Code
[go]$$B 19x19 board
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . O X X . . . X . O . . . O . . . . |
$$ | . . O , . O . . . , . . . . . , X . . |
$$ | . . O X X X . . a a . . . O O X . . . |
$$ | . X O O . . . . . . . . . . X . . . . |
$$ | . X O O 1 . . . . . . . . . X . . . . |
$$ | . . X O B O . . . . . . . . . . . . . |
$$ | . . X X O B . . . . . . . . . . . . . |
$$ | . X . O O . . . . , . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . O O O O . W . . . . . . . . X O . . |
$$ | . X X . X . . . . . . . . . . X O . . |
$$ | . . X . X . . . . . . . . . . X O . . |
$$ | . . . , O . . W . , . X . . . , O . . |
$$ | . . . X O . . . . . O . . X . X X O . |
$$ | . . . X . . . . . . . . . . . . . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I don't understand the concern about E12. Sure, it is a nuisance, but little more for white has the driving tesuji to get out. And if black tries too hard, he is just playing toothpaste go.

So I tend to like Illuck's suggestion of reducing the right side with something around the point marked 'a'.



But why would Black play that rather vulgar :b1: at all?

It's the aji of the atari on the other side that makes it hard for White to stake anything in the middle, giving a much higher chance it becomes Black's playground later. The fighting over the single stones actually caught in that engagement is petty cash, but Black's built quite a useful center facing thickness where White doesn't have clear equality from his side.

I personally don't think the left side is as urgent as the lower side (one of my many weak hats is on clearly), but if I was to play on the left, I'd rather render the two marked Black stones useless whilst simultaneously guaranteeing my group unconditional cheerfulness. It also means that a Black move around the "a" area doesn't make :b1: start to look dangerous, and it means White doesn't have to worry about having two weak groups if the connection between the marked White stones is challened.

A move around there just seems to do a great deal for White's long term bad aji - probably not urgent enough if it wasn't for the fact that it completely settles some important White stones - it just feels thick enough to play.
Post Reply