Another thing I was going to mention but I forgot was the fact that he doesn't watch his shield/health. I'm not sure if theres health packs in MLG game modes, but I do know many of those deaths would have been avoided if he didn't charge in without a shield.
Makes me wonder if he was doing a "fake rage".
I can tell why he's angry. He spams the trigger and uses both his grenades on the first enemy he sees, sometimes resulting in a bad throw causing it to explode in his face. This isn't Halo 3 where you can repeatedly tap the trigger with the battle rifle
with little effect. Not bashing Halo 3, just stating a fact. Whether or not you like that type of game play is up to you, it's two different games.