sorry havent read it all but thought i should just point out ,yes use finger pointing as a guide but until someone sees you shooting who knows what to look for its very difficult to have one answer suits all .
its a moving target ,how the eyes pick it up ,does one eye pick up the clay quicker than the other ,that could be the eyes or how the gun is mounted theres loads of different variations you need to know exactly whats happening before trying to cure it .
one thing which ive read here which works very well for me is having a high stock , i try to keep a simple style that i dont need to think about and use it till it became second nature and then just think of the clay and nothing else
not saying the above works for everyone but its just my 2p worth