I coach U-18/varsity boys and we do a limited amount of heading "drills" in practice. Trust me, my kids can't afford to kill any brain cells so I don't take any chances.
I played numerous positions through my high school and college career but I use to avoid heading the ball when I played sweeper and the opposing keeper punted the ball. You can't tell me doing that 10-15 times a game can be good for the brain. I know technique has a lot to do with whether it hurts or not, but even if it doesn't hurt the player, it has to rattle the brain a little.
