to me the greatest risk would be having such a narrow base when the rear leg is drawn forward to meet he lead. granted its a moment in time and a training process, and to drive more power into a strike, so hopefully you are not exposed as you follow through and are 'successful', however (taken as a snapshot in time) with such a narrow base you can be taken down at will.

although no one would retain that position for more than a moment, it can still be capitolized on by the right person at the right time.

its always a risk vs. reward type of situation.