re-action hand , what is it good for?

[Shorin Ryuu]

I mean reaching toward your waist to withdraw your weapon in your holster or something.

Hmm...While it could be possible, that sounds a bit strange to me. I would think there are better ways of moving the hand to draw a weapon from a holster or other position. It just doesn't seem to lend itself to drawing a weapon with a palm-up fist like that.