There are all sorts of problems with this though. First off - escalation. Player A does something Player B doesn't like. So, Player A doesn't get healed (for example). You're going to tell me that this won't cause any arguments at your table? It sure as heck will drag play to a grinding halt at mine as Player A bitches and whines for the next hour about how he can't play the game and how everyone else just sucks. Or, worse yet, Player A's character gets flat out killed. Yeah, that's not going to cause any hard feelings at the table. :/
Keeping stuff like this in character is the absolute WORST gaming advice ever. It will NEVER resolve in character and will lead to garbage play experiences.
We do that all the time. No Evils is a pretty standard table rule. The notion that you get to play whatever you want regardless of the group is disruptive and frankly a bad player.