I thought it was going uncharacteristically well for me up until one point.
It had its ups and downs, but according to AI move 75 was the nail in the coffin.
I’m trying to get a better feeling on this, the point of that move would have been to prevent 2 eyes on upper left, right?
If so,
A. Is there a way white could counter B12 or is it a defining move?
B. I don’t know what my lacking was exactly, is this about life and death? I mean, where should I look to for that mistake? I can tell my shortcomings generally, but this seems specific and “improve at everything” is overwhelming .
Yes, playing move 75 at C12 would kill, and it would kill in a very “clean” manner (you are very strong outside) with no counterattacking chances. I gave you some sequences in a review. After B12 you cannot kill anymore. The difference with the game is about 25 points.
Since the group is surrounded and isolated from the outside, it is a typical tsumego (life and death) situation. Progressing for those situations require:
Doing life and death problems, and
Paying attention when a group become surrounded to read if it is dead / alive.
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