DietersMistakesIn2022/Solution1

Move 73 - my mistake  

In the game I chose (or a in /Problem1) and let the cutting stone be a burden for White. KataGo thought this was a big mistake and I should have played b instead:

Solution - var 1  

Surround in sente If White captures two stones, effectively kills.

Solution - var 2  

White can live with this sequence but then Black has still sente to deal with the lower side, using his central thickness.

Failure to surround and harass a big group, forcing it to live small or be killed.