All right, here's an example. X makes a post on one side of a position. Y makes a thought-provoking reply on the other side. X replies with "So what's your point?" X either fails at reading comprehension, or X is trying to make it look like Y didn't have a point, because X doesn't have a good reply to Y's point, and X wants everybody else to not notice that Y actually had a good point.

I hate seeing that. It's a bad-faith argument. It's the sign of someone who's just there to argue, not to have a curious conversation. That is, it's a sign of someone who isn't within the spirit of the site guidelines.

No, I don't think this is just my personal bias against that style of posting. It's fake and juvenile, and it has no place on HN.

Another way you can tell: When they're replying to 20 comments with the same 2 or 3 talking points. That's someone who's there to do battle, not to have a conversation. They aren't really replying to the 20 comments, either - they're just spraying the same canned responses all over the place. That's not a conversation; that's a tape recorder in transmit-only mode.