Forgive me for being so incredibly wrong.
Gee, you guys are absolute football geniuses. Why aren't you doing it for a living?
you must feel like such a genius on sundays between the hours of 1-4pm while you sit there on your couch with one hand down your pants and the other buried in a bag of doritos, and stare at your TV and say "Run Play."
While youre doing that, defensive coordinators around the league are sitting up in their coaching boxes with an endless stream of stats, information, player personnel combos and other things while they are trying to decipher if the offense is running a "53 blue speed 6 front over" or a "sprint rex 8-zac chicago", determining what to do based on the opponents previous situations, and what blitz packages to send with the current personnel the offense is using.all of this going on every 30 seconds, knowing each and every decision he makes has HUGE ramifications.
But yes, continue to sit there and explain how you (random guy who spends his time on an internet forum) could do a much better job