Life In 19x19

Hello,

Would you mind having a look at the game below? During the game, I thought I was ahead after move 61, which connected my groups and created an isolated White group. I'm not so sure now, though. White gained a lot of territory on the left while chasing my groups around.

Quick thoughts:

Black 143: O1/P1 is one of those double-sente moves that stuck around on the board way too long. You should strive to play double-sente moves like this as early as possible, so that your opponent doesn't play it first.

White 158 is really bad. If white just plays the solid connection at J18 then white will have the sente move of L19 later.

Black 161 is not necessary. If black instead tenukies and plays S14, then when you consider the sente followup it's a swing of 7 points.

is inconsistent and very bad, letting B capture the previous cutting stone with a ponnuki. If W does not like the prospects of a fight, he should not cut in the first place. W could also consider cutting at E6 (but not E5) instead of G5 at move 20. After the ponnuki, B is definitely in the lead.

Let's evaluate the board position after move 24. What are the important features?

• B has massive thickness from the ponnuki, so the two W stones on the lower side look pretty weak. W really wants to slide to Q2, to live with good shape and territory. Compare that to a B move at P2, undercutting the W shape. The difference is enormous.
  
  The B stone at D6 has been greatly weakened and is now the least valuable stone on the board. It still has lots of aji, but its best use is probably to slow W development. B should treat this stone lightly.

For these reasons, seems to me like an overplay. Locally, jumping lightly to D8 would be better. Then, if W wedges, B connects on the outside and gladly lets W capture one stone. Globally, P2 or P3 look like the vital move, making maximum use of the B ponnuki. Other big moves like C14 or F16 or Q14 or R9 are less vital but still larger than the actual B move. After move 30, W is back in the game, with good fighting chances. Are the three B stones at D8 an asset or a liability?

In the middle game fighting, B had several groups to chase, but played some moves which look slack to me: (H15), (J8), (L8). These moves are all nice shape, but they do not really accomplish much. Assuming W lives in the center, these moves can easily become dame. In contrast, (P2) was a perfect attacking move, making real territory while attacking. (Unfortunately was a blunder, throwing away the attack.)

In the endgame, both players ignored some very big plays for a long time. W won the game by eventually getting almost all of the important yose moves: E2, S7, P1, K18, S14. Replaying the endgame as B would be a good exercise, to see how much the score would change with better play.

I'm not even at OP's level, but I would think that B11 or at the very least B13 might be at Q14?

Click Here To Show Diagram Code

[go]$$Bcm61
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O O O . . . . . . X . . . . . |
$$ | . . . O X X . . . , . . . . . X . . . |
$$ | . O O . . . . X . . . . . . . . X . . |
$$ | . . X X . X . . . . . . . . . X O . . |
$$ | . O . X . . . . . . . . . . . . O . . |
$$ | . . O X W . W . a . . . . . . . . . . |
$$ | . O X O X W . . . . . . . . . . O . . |
$$ | . O X 1 X . W . . . . . . . . , . . . |
$$ | . . O . . X X . . . . . . . . . . . . |
$$ | . . . X X . . . . . . . . . . . . . . |
$$ | . . . X O . . . . . . . . . . . . . . |
$$ | . . . X O . X . . . . . . . . . X . . |
$$ | . O . . O X . X . . . . . . . . . . . |
$$ | . . . O O O X . . , . . . . . X . . . |
$$ | . . . . O X X . . . O . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

is not a good place to evaluate the position, because the floating stones are unstable. Much will depend upon how well Black attacks them and White defends them. Since White has sente, things look good for White. Instead of taking the White stone, Black should probably attack the floating stones; at "a", for instance.

Click Here To Show Diagram Code

[go]$$Wcm62
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O O O . . . . . . X . . . . . |
$$ | . . . O X X . . . , . . . . . X . . . |
$$ | . O O . . . . X . . . . . . . . X . . |
$$ | . . X X . X . . . . . . . . . X O . . |
$$ | . O . X . . . . . . . . . . . . O . . |
$$ | . . O X O . O . 2 . . . . . . . . . . |
$$ | . O X . X O . . . . . . . . . . O . . |
$$ | . O X X X . O . . , . . . . . , . . . |
$$ | . 4 O 1 3 X X . . . . . . . . . . . . |
$$ | . 6 5 X X . . . . . . . . . . . . . . |
$$ | . 9 7 X O . . . . . . . . . . . . . . |
$$ | . 0 8 X O . X . . . . . . . . . X . . |
$$ | . O . . O X . X . . . . . . . . . . . |
$$ | . . . O O O X . . , . . . . . X . . . |
$$ | . . . . O X X . . . O . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

But is a useless threat. Black can attack with something like . Then if Black has a ladder.

Click Here To Show Diagram Code

[go]$$Bcm61
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O O O . . . . . . X . . . . . |
$$ | . . . O X X . . 6 , . . . . . X . . . |
$$ | . O O . . . . X 7 . . . . . . . X . . |
$$ | . . X X . X . . . . . . . . . X O . . |
$$ | . O . X . . . . . . . . . . . . O . . |
$$ | . . O X O . O . . . . . . . . . . . . |
$$ | . O X . X O . . . . . . . . . . O . . |
$$ | . O X X X 3 O 4 . 8 . . . . . , . . . |
$$ | . . O O . X X . . . . . . . . . . . . |
$$ | . . . X X . . . 5 . . . . . . . . . . |
$$ | . . . X O . . . . . . . . . . . . . . |
$$ | . . . X O . X . . . . . . . . . X . . |
$$ | . O . . O X . X . . . . . . . . . . . |
$$ | . . . O O O X . . , . . . . . X . . . |
$$ | . . . . O X X . . . O . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

But then is horrid. It answers White's non-existent threat and invites White to strengthen his group with . is an attack of sorts, but a capping play at 68 would be stronger. We call such a play topping the tree. After White has taken the lead.

Thanks to all! This advice is very helpful.