Life In 19x19

For first diagram, if o5 is enough to win, why not? BlindGroup, how did you count top left? Like Knotwilg suggested it's unsettled, but even so I wouldn't play there as it's essentially a very large endgame move with no effect on the rest of the board and if you o5, white lives in gote, and you get another move to close centre and reduce lower side you presumably win. Also from a psychological standpoint maybe white doesn't realise it can live, in which case you can kill it later (a bit of a naughty approach, but effective).

As for 2nd, I spy troubles. Note ugly 5 here (making empty triangle, often a is better) was key to take liberty (so capturing 2 stones is sente) and just manage to live in my first kill attempt. Maybe some preparation at b could make it harder to connect to left.

Click Here To Show Diagram Code

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

Click Here To Show Diagram Code

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

Click Here To Show Diagram Code

[go]$$Bc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O X . X . . . . . . . O . . . . |
$$ | . . O O X . . . . . . O O O X O O O . |
$$ | . . . X . X X . . X . . X X X X X O . |
$$ | . . X X . . . X X . . . . . . . X X . |
$$ | . . . O X X X O O X . . . . . . O . . |
$$ | . X X . . O O . O X . . . . . . . . . |
$$ | . O X . . . . . O . . . . . . . X . . |
$$ | O . O X . . . O . . X . . . . . . . . |
$$ | . O O X . . . . . , . X . X . , . . . |
$$ | . O X . X O . . . X O O O . . X . . . |
$$ | . O X . . O . O . X O X . O . . . . . |
$$ | . O X . . . . . O O X X . O X . . . . |
$$ | O X X . . . X . O X . X . O . X X . . |
$$ | . O X . . . X . . X . X X O . X O . . |
$$ | . O X O X X O O O O X X . . O O . . . |
$$ | . X O X X O X . . X O X . O . . . . . |
$$ | . O O O O O . . 2 O 1 . 3 4 . . . . . |
$$ | . . . . . . . . . . . 5 . . . . . . . |
$$ +---------------------------------------+[/go]

Knotwilg wrote:Your game is a perfect example for your question.

I think all eyes go immediately to the top left corner: have you really figured out what happens if White plays the 2-2 point there (B18) ? I can't do that in just a few second.

You're right. That's another example of an unnecessary risk. I did spend a little time reading that out when I was playing in that local area, and decided that it was dead. This is a good example of not taking into account the accuracy of my initial assessment. This I think is also what is so hard about this aspect of the game. I'm sure at some point I'll be able to look at this position and know it's status with certainty, but before then, it's very hard to know when something is not as certain as you think it is...

As an aside, my plan for the 2-2 was the following:

Click Here To Show Diagram Code

[go]$$Bc
$$ +---------------------
$$ | . d 1 2 . . . . . .
$$ | c W . O X . X . . .
$$ | b a O O X . . . . .
$$ | . 3 . X . X X . . X
$$ | . . X X . . . X X .
$$ | . . . O X X X O O X
$$ | . X X . . O O . O X[/go]

Then, white has three options:
1. If white D, black C.
2. If white A, black B.
3. If white D, black D.

I had gotten this far in the game, but looking at it now, it's a complicated position. I did not, for example, think of what happens if white plays 2 at 3. It's complicated enough that I could have made a mistake. I think I need to be more cognizant of the limits of my reading abilities.

BlindGroup wrote:I did not, for example, think of what happens if white plays 2 at 3.

Indeed, white's best move.