Coach P is spot on. I tell my players to do the right thing, regardless of what someone else is doing. (It's the same conversation I've had time and again with my children.) If they get clipped from behind, play the game correctly regardless if there is a foul called or not. I might agree or disagree with a referee's call, but there is no reason to embarass myself, my team, or the referee by making a scene on the sidelines. Have I had players carded for dissent? Yes. I also have a good talk with them about how their actions have consequences.