The weight at setup is CRITICAL. The misconception of having the weight on the balls of your feet is a compensation to correct another problem.
The correct weight distribution is just like a quarter back or any other athlete… “ATHLETIC”. What I mean by this is STRAIGHT DOWN as if you were guarding someone in basketball or a quarter back ready to have the ball hiked to him. The legs are ready and balanced and you could move in any direction.
If you setup out of balance (balls of your feet) your body will try to “Right” itself during the swing and you will be moving all over trying to center yourself.
If you setup IN BALANCE you will not have to make this adjustment during the swing and will much more consistent with one less compensation to worry about. Also, gravity will keep you centered and in place.