"Take a look at this photo and tell me that it is possible to get into this position without fully cocking the lead wrist:"
Yes. I just did it. Maybe it's just me but my wrist will only "cock" a couple
of degrees anyway in neutral position with thumb pressed to forefinger. The only
way I can get an appreciable angle between my hand and forearm is by cupping or
bowing. There just isn't much cocking available to me.
Now if I release the thumb from the forefinger the thumb will pull out to nearly
90 degrees but that isn't how I grip the club and that isn't wrist cock.