Sorry guys, was in a hurry and had to leave. Don't even know why I didn't post how to do it. It's only a theater mode glitch.

Jump off a cliff during gameplay, and then play your game normally after you respawn. After the match, put the game you just placed in your fileshare, and play it back in theater mode. Now, be in first person mode, and when you fall of the cliff, when you die, switch to third person... and you should be sickwalking.

Might be funny for some good frag videos or something. Enjoy.