Sorry to disagree, but... EVERYONE has raged one point in there life if you play the game long enough. Another thing... Pro's rage at each other, like all the time. It is a bit more polite I guess to teammates, but not really. People who take it seriously generally rage more than people who play casually. I guess your assumption comes from the general population of HoN not being SUPER pro, and the terrible community being all ragers. That makes you THINK everyone who rages = bad, but even good players rage at bad players. It's sadly the gaming society.
Cheers
-JaySongs