[Yoda]

Am I correct in assuming that this 'dynamic' weight shift is mandatory for full shots? Or in other words, when looking at video of me hitting a Driver, must there be a visible shift to the left 2-4 frames prior to the hands starting down, and if I'm not doing this, am I not shifting your weight properly?

That's right, Andy. In Pivot Strokes, the Downstroke begins at the ground (the Feet) and sequences upward through the Knees, Hips and Shoulders. The Hip Action (Hips pull Shoulders) shifts the weight and maintains the On Plane Right Shoulder during the Start Down. This Body Action pulls the Arms, and the Arms pull the Hands (which have experienced a momentary static period that defines the Top).