Doesn't policing yourself on so many things take the fun out of the game?
It does for me. Actually, I insist on playing a game with the rules provided. You can't police other people in multiplayer anyway and I like MP. So I shove and I dip and I stealth cheese even if I don't feel good about it.
It's also about playing a game as well as you can, mastering it so to speak. You can't master a game if it's so easy you have to impose restrictions on yourself. So while I can stealth shove everyone into a pit, it doesn't feel good or rewarding.