[drewitgolf]

My question were: Are the difference between 10-18-A and 10-18-C-1 the start-up-swivel vs. gradual turning with the hinge action?

Sorry Thom,

In my haste to answer, I compared 10-18-A to 10-18-C-2, instead of 10-18-C-1. But to answer your question, you are correct.

Mr. Kelley revised 10-18-C for the sixth edition. In fact if you substitute (last line) NO HAND MOVEMENT for NO HAND MOTION during the Stroke, it may make more sense. 10-18-C-2 does not involve deliberately Turning your Wrists to the Plane in Start Up like Standard Wrist Action.