TGM teachers that I know usually recommend 10-18-C (Single Wrist Cock) for their students. The advantage of this is... "Because their is actually NO HAND MOTION during the Stroke, Clubhead Fix alignment remains undisturbed."
There are many teachers, however, that do recommend the cocking of both wrists. This obviously can work, because there are many very good players that do so... Mickelson, Daly... and many of Mr. Leadbetter's and also probably Mr. O'Grady's students, among others.
There seem to be two versions of this type of WRIST COCK.
#1-- A Double Cocked LEFT WRIST and Double Cocked RIGHT WRIST
#2-- A Flat LEFT WRIST and a Cocked RIGHT WRIST
In TGM terms... describe the mechanics, physics, workings, etc. of the BOTH WRIST COCKED procedure.
(This is not meant to argue that the Both Wrists Cocked mechanic is better, but I think it would be good to know how this works.)