If I recall correctly, there was a point where he asked for some feedback on the Quake 2 weapon models he had created. I exchanged some emails with him about them, mostly criticizing the rocket launcher. He was very cool in the way he dealt with my feedback, even if I wasn't always as politically correct as I probably should have been. Heck, I was still young back then.
He took the time to describe what he was going for with his designs. He basically went out of his way to describe why things looked the way they did. There was always logic behind his decisions. And he was definitely a master at his craft.
The best compliment I can give him was the first time I saw the female model from Quake 2 with the ponytail. It was the first time the thought of ever "F'ing" a polygon ever crossed my mind.