Originally Posted by
WC1277
The problem with using the same arm you're attacking with to deflect and then continue the attack is that it's too many movements and lost timing beats. Once the attacking arm gets moved off the line and switches to deflection it inherently loses a 'beat'. It's far more efficient to switch.
We only have two arms. The shoulder that is forward in an attack becomes active and committed, so to speak. You nervous system has to turn it off, then back on to change course. Your rear shoulder/arm, however, is already turned off, so it inherently has a faster reaction time.
This concept is the whole point of the majority of the forms, especially the punching. When you punch in the forms, one elbow pushes out, one elbow pulls in. The exact same motion as pulling a rope. Unless you can figure out a way to pull a rope with one arm and not allow any slack, you're already going against body mechanics and timing.
It's not Wing Chun, it's an add-on....