I agree one of the absolute keys (difference in good pro vs amateur) is the ability to lock the hands to the shoulder turn at the start of the swing. However, in Gonzalez case (and many others) I do not see independent hand action at this point in the swing. To me the bat head is travelling in a logical arc caused by the fact that it is locked in place.
Using scap load as a way to create the lock? Is there a physiological principle at work here or something else?