It's a single player game open to modding. When you can make the rules up as you go, how do you even define cheating? At first I used TCL to get through a lot of invisible walls, but later decided they are present for a reason (even if I don't agree with it on principle). Also, since I've gotten used to shooters with regular checkpoints, I sometimes forget to hit F5 after a few tough fights. In those cases, I'll use TGM to "reset the playing field" so to speak. If anything though, I put more in to making things harder.