I pretty much agree with that idea. If you look at quicks, spinners and even dibbly dobblies the best exponents always have a loose grip, limber wrist and a relaxed natural action.What do you reckon then - what are the main faults that reduce spin? Do you not think that a technically correct whole action which might include the 180 rotation doesn't equate to a potentially better outcome? I always think of it in terms of using a whip, which starts off with a good solid base and ends up with all the energy going through to the crack at the end. I'm sure someone who is an expert with a whip would be far more accurate and powerful because of a combination of similar attributes, which are whole action/whole body?
Main faults are usually the opposite of that, tight grip, stiff wrist and a rigid action. Most of these come from people doing their best to apply what they've been told or seen but not quite getting there.
Still, that's me, there's people here who I'm sure have different ideas.