Sarcasm I don't mind—gotta eat my own food, obviously. However, shifting the discussion is a different matter, while I was replying to one specific claim. On top of that, the arguments about material harm, that you've mentioned, are utterly worn-out go-to points of the anti-copyright folks. I do have my opinion on whether they make much sense and are worth repeating in each discussion on piracy, but that's another topic.
I see. I'm not usually involved in conversations on this topic so I'm not really aware of whats considered an argument that is no longer valid from over-use.
I don't think it was shifting the discussion either. You made a sort of sarcastic remark about getting stabbed, I brought the focus back on going to jail over the topic at hand.