I'm terrible, and I have played with mostly terrible people. By the time I met him he was patient with all us horrifically bad people and was willing to play on a team with people who weren't as good as him. A++ for dflame if you aren't a great team, wish you had a carry, and are willing to say he's not terrible at the aiming thing on occasion.
He doesn't take mean criticism well. He'll mope over getting constructive criticism, but I think he hears you best if you aren't trying to tell him he's shit when really he just needs some thing worked on.