I don't think it makes a huge difference with or without the rotation, people have been successful either way. Rotating seems to bring slightly different muscles into play and the body mechanics change in a subtle way so people will probably have a preference for what they're used to.

Solid post!!

I think there is a brief analysis in one of Hee Ill Cho's books on the affect of wrist rotation and punching power.

In the grand scheme of things, I don't think it adds a lot to the punch. Its become an aesthetics, technical thing more that anything, I think. The power of the punch comes from the ground, driving up through the hips and core, and is transferred through the arm, with the fist merely acting as the tool that distributes the power.

If I think about it, I'll look into that book and see what I can find.

Solid post!!