I've done very little organized training, other than martial arts. Mostly my "training" has just been doing things like shoot/don't shoot drills, as well as shooting one handed with either hand, reloading with one hand, and doing all of this from different positions of cover. I've never really seen much need for anything further than that.
Although, I do have tremendous respect for modern military tactics. I read what I think was the Marine scouting and patrolling manual. Very well thought out strategies.