Chris, I don't believe people have 4 or 5 screen names. This site gets a few Trolls, we would have many of them back during the yahoo days of debates. You probably never participated in those, they came about in 2000. Invictus is a fine example of a troll.
The only screen name that brought about curiosity for me was WUS, but I didn't dwell or dissect her comments. I learned a long time ago to react to the message, the messenger truly matters not. I think people use screen names to maintain anonymity because they choose to remain impersonal.