Where did I say 'only' the left? The right supports the left, but not at the 'start' of the downswing.... that list is the sequence of the cracking whip. Does anyone here think that isn't accurate - lets here it. Regardless of what the right side does, that list must happen in sequence (and yes, the right side is just as important)
TGM is a great source of the 'what', and the 'why', but not the 'how' - so no, I don't consider it the greatest thing since sliced bread like some.... which isn't to say I don'think it is one of the better contributions to the swing, only that it isn't everything.... if it were, people could just read it and be scratch players without any help.
An oustanding tool\framework for instruction, but not the be all end all....