Well, he doesn't just go around ruining people's lives for fun; that is to say, he would only do so if he had a lot to gain from it, such as if that person was standing between him and a promotion.  He's much more likely to turn a couple people against each other, as he can always benefit from someone else's social misfortune, but really only if those two people were probably going to clash anyway.  In sum, he's a catalyst.