I have contemplated this same mod. The biggest problem I saw was if it were used in an online multiplayer game. In most first person shooter games other players are able to go back and review past matches. I assume that moderators have even better capabilities. Let's say you are using a semi automatic rifle and firing more rapidly than humanly possible someone could catch on. Every move you make in a game is viewable by moderators, developers, other players, etc. There is a possibility you could be suspended or banned from the PSN if caught.