Look for double threats
This article is from one of my insei games in Japan. I am playing White, and in Diagram 1 Black has just cut with 1 and 3. This is an overplay for Black, but as it is the case with overplays, if we don't find a sharp response they turn out well for the player who overplayed.
There is no hard rule about how to punish an overplay; actually it's the postmortem analysis that may prove something an overplay; during the game it is best to just concentrate on looking for weaknesses in the opponent's formation, and ideally we may be able to find a double threat. When I start by telling myself "My opponent has just made an overplay... Have to punish him... Have to punish him..." I normally lose focus and make mistakes.
Dia. 1
First of all, the most straightforward way to capture, the ladder, doesn't work, as Diagram 2 shows.
Dia. 2
Since White cannot capture Black's cutting stone, then it's time for White to think about defending his own isolated stone on the left side. This is a good approach, and White 4 in Diagram 3 is what I played in the game - except that this is too mild and it's missing a nice opportunity: Black can play A next, for instance, and given that he has the nozoki at B to take advantage of White's weakness, Black is in good shape to fight in the center.
Can you find a better alternative for White 4 in Diagram 3?
Dia. 3
