It's easy to at least get to DH3 in reply to anything. For example if they say, "you are an idiot" you can contradict them (close enough) by saying, "you haven't supported that statement". If they question your tone or authority, you can contradict by saying that isn't relevant to what position is true.
edit: btw my experience is that more often than not i get downvoted if i do this
About the downvoting, maybe it's because they feel you're making a predictable contradiction to a painfully obvious inane trolling? If somebody says something like "you are an idiot", just let them get downmodded alone.
edit: btw my experience is that more often than not i get downvoted if i do this