Coaches rules are coaches rules, but coach has no business talking to any player like that. If coaches want to be respected, they in turn have to give respect. You can be stern and still get respect, or you can be a jerk and get none. Kids are not stupid and most will not give the coach their best when made to feel like they have been embarrassed. I find that most coaches that tend to go overboard are usually self centered, power hungry individuals. They have little control over some issues in their lives, so they need complete control on the field. I am one that believes that coach should get respect just because he is the coach. But if he is rude, nasty, a bully or in any way jeopardizes the health or safety of my son, I will be the first one into the AD's office.