As I read this article, I almost laughed out loud at what the captain does. Before the flamers get their torches up, I KNOW they didn't get the idea from GW or anything stupid like that. The explanation of a captain, however, does give a good explanation of what a paragon does for the team.
Because Paragons are the first class to be copied from game to game.
The key to developing a good game is to steal ideas from other games. That's just how it works. It's evident in Guild Ward, Lord of the Rings Online, World of Warcraft, Runescape, etc.