Prospective football stringers at my old shop had to shadow me for a game before we'd set them free on their own assignment. Two stories:
-- Young female in college goes to game with me, we're on the sidelines. Big lineman is standing near us, shoes covered with tape. She says "wow, he's playing with two broken ankles?" That, in addition to having to explain the concept of downs, didn't earn her any future work.
-- Old fella follows me for a half, then asks if he can go home at halftime. Fine by me, he seemed to understand everything. Well, he went home and died.