For me the process goes something like, "Hey! That's a really good point. Does this person have a high karma? If so, perhaps I've seen them before but haven't seen the name around." Other times it's, "Wow, this person sounds snotty and wretched. I hope they've got a low karma score to compensate. Perhaps even a negative. Oh, damn, they've got 24,000, I'm arguing with nickb again." Once every few months, it's "Look, this person's disagreeing with this 'unalone' bloke, they click the name, and - look! - he can't possibly be wrong with that karma score." I like to delude myself.