[EdZ]

This has the makings of a great thread.

I say the 10-18-C-1 backstroke is indistinguishable from 10-18-A. The amount of true wrist rotation which is suppose to distinguish between the two is the same. The only difference is that 10-18-C-1 happens more gradually and 10-18-A more suddenly in the beginning of the stroke.

One piece of advice for those trying to apply this info to their own swing. Use the wrist action you're most comfortable with to keep the Clubshaft On Plane. I see so many people who are doing well, and then they learn about Standard Wrist Action (Start Up Swivel) and they start going under plane and all sorts of compensations start creeping in.

True - it can be very easy to turn too much and end up off/under plane. That said, there is a 'big' difference between the two (startup swivel vs none).

I tend to 'feel' this via my left shoulder and the clear feel of getting 'under' the shaft, while really feeling the 'line of the left arm/club/wristcock going 'UP' the plane.

The feel for that 'line' is the key benefit of the medicus 2000 IMO. The trick is getting the 'up plane' while not letting the clubhead get behind your hands in the startup.

The swinger's feel for the left arm flying wedge (loading the left wrist - 10-18-A), the hitter's feel for the right arm flying wedge (loading the right elbow - 10-18-C)