Left hand rotation through the impact zone

[Jeff]

12PB

I presume a neutral grip with the clubface parallel to the back of the flat left wrist-hand. I believe that the clubface rotates about 90 degrees between the delivery position (third parallel) and impact, and about another 90 degrees between impact and the fourth parallel position when the toe points up.

It's not critical whether it is 180 degrees or slightly less than 180 degrees eg. 160 degrees. My question relates to whether the 160-180 degree rotation is due to active movements below elbow level or whether it is primarily due to movements occurring at shoulder level +/- the effects of torso rotation.

Jeff.