Can only speak from my personal experiences and those of who I talk to but I disagree here. The individual position drill work yes is maybe 80% the same across all teams but the 20% difference is what separates the great coaches from the rest.
The individual attention to each players technique and giving feedback on how to make it better is the player development we all talk about.
OLine coaches teaching first steps based on DLine position, hand placement on the initial punch, WR technique getting of the ball on press coverage, when to double move, when to lower hips getting out of breaks, teaching RB’s when and how to jump cut, teach them second level vision etc, etc. some coaches don’t really notice some of the finer points or can’t see it on film to coach it properly.
