I don't think CF produces an over roll. It doesn't produce a roll at all. It produces angled hinging.
I actually thought that CF (or actually angular speed) would add inertia and make it harder to close the club than when it is at rest. But after a brief check on www on angular inertia, coreolis force etc I think the work requred is the same in any case.
The machine have to close the club directly. A level hip probably helps for precision. And a good pair of wedges. A little initial torque from the top or somewhere in the down stroke. And keeping the left wrist vertical throughout. Whether the closing is freewheeling or adjusted by the hands isn't a biggie. The hands know their impact alignments whether they are right or wrong, and the work involved in closing the club is anyway close to nil.
All the cf will do is keep the club moving in circles at a constant speed. It's the radial pp forces and possibly a momentum at the hinge pin that increases rotary speed.
If you let go of CF the club will go way left. Spinning around its longitudinal MOI befor it lands in the dirt.
When I said above that CF produces angled hinging I wasn't intending to exclude horizontal hinging. The spin can be horizontal and therefore also the hinging can be horizontal. Or vertical. if the plane is vertical But not dual.
Perhaps my post's title or question is incorrectly worded from a science point of view then. When I say CF perhaps I should say Radial Force or Rotational force or some such thing.
I think I get what you are saying in last paragraph. So assuming we are on an Inclined Plane somewhere in between vertical and horizontal, an Angled Hinge will tend towards the characteristics of the closest plane be it vertical or horizontal. Is that what you mean?
In that case, Homer's string demonstration, didnt/couldnt display horizontal hinging but rather an Angled Hinge.
So I start thinking: Maybe the rotation doesn't care whether the club face is vertical at all times. So I do a little experiment. You can do it to:
Take aquired motion with your right hand. From horizontal to horizontal. Flat vertical hand at all times. Anti clockwise rotation right? Then turn around 180% and complete the circle. Not down and up. But up and back to horizontal. Complete the circle. Clock wise rotation on the upper half.
I don't see how this - anti clock wise and clock wise can alternate without additional forces doing something. Can earth gravity do it? Maybe but I don't see how at the moment.