Was it on the same TV? Has your friend played Halo 2 before? How well did you know the map you were playing on? I'm a huge Halo fan, but I always question why people think they're so good at Halo when they don't face fair fights. Playing on the same TV allows for screen watching. Knowing your way around a map gives you a huge advantage, especially to someone who doesn't play as much as you do. I'm only around a 30 in matchmaking, but I know that when I play my friends they don't stand a chance. I'm not saying playing on Live is perfect; there are plenty of standbyers and modders, but it does take away the problems I listed above, since nearly everyone is as familiar with the map as everyone else, and clearly they play a lot of Halo. I'm not questioning your skills, it's just that playing the person next to you is quite different.
yeah it was on the same screen. but still, my friend also had the same advantage. hes coming over again for a rematch. ill post the scores when the smoke clears