Name-calling is pointless and only serves to degrade the other person and their position, regardless of whether their points hold weight or not, which isn't what a debate is about. If you have a sound argument, there is no need to use insults. People forget the reason these rules of debating exist is to lessen the emphasis on shit throwing and appeals to emotion and make it as much about the actual issues themselves, and whether a position makes logical sense, as possible.