[Lawtan]

I'd actually chalk that up to defensiveness. If they don't think they stole it, than a "Hey! You !@#$ing stole my work!" would automatically have the human defensive reaction of "No I $%^&ing didn't."

Now if it was said "Umm, I can tell that you traced part of my work. Please either cite my work or take yours down." and they responded similarly, they are a kingly jerkass.

There was one person who stated that they were receiving lies from people that something was their work (When he knew it was someone else), and as such apologized, but he would not cite something when he was not sure whose it was. (This is another socket wrench here. The kings of jerks try to tell anyone willing to cite that a work is theirs/from theirs when it is not, for incitement and attention)