Theory: wing chun trap

The wing chun trap has to do with getting your opponent to move in a predictable way.

If you were to pak the first punch you have a good idea of when the second punch will be coming.  The second punch comes after the first punch with withdrawn.  You have to feel this happening.

The hand is quicker then the eye, so you can't rely on it to predict the next punch.

Any non- committed block does not require the wing chun trap.  The non-committed block is at the fore front of the wing chun trap.  It is there to sense when the opportunity reveals itself.  Once inside the trap, it is best to switch to a committed movement so you can finish your opponent.