Of the current world class players that I can think of...Scott Hoch is the STEEPEST and Dana Quigley(Alan Doyle close) is the FLATTEST on their backswing planes. The rest are somewhere in the middle, although FLATISH seems to be making a comeback in popularity.
How about a discussion on what makes these two extremes work...GRIP, SHOULDER TURN, HIP TURN, PLANE SHIFTS, DELIVERY LINES, etc. Maybe if the two extremes can be understood, then the middle(with hopefully less compensations) can be better understood.
Hybrid Mode
