Yup....played from the age of 16...until I suffered a head injury and contracted epilepsy a year ago at the age of 21. I now coach in a part time capacity as I've had to get a few things on track over the past year I've had it...hoping to make it full time soon
my coach was an American who played himself through high school but broke his back in an accident which prevented him from playing further. One of my close acquaintances as a coach played 'ball at Navy.
Obviously the teams and leagues we have over aren't anywhere close to NFL standards, but the football concepts aren't any different...and it's not hard to understand the concepts between cover two, three, quarters etc. it's just very difficult to actually see what's going on with broadcast footage...you need the coaches tape. It took me at least ten replays of the broadcast footage to see what was actually going on because you can't see everyone.
I'm an amateur of course
FYI for anyone who likes furthering their knowledge....'Take Your Eye Of The Ball' by Pat Kirwan is a phenomenal book when it comes to teaching you about concepts of the game.