You find bad papers in every area. To criticize a paper's hypothesis which the authors explicitly show they didn't get good correlation for (and was surprised by), seems... well, a bit weird.

Can you SHOW they are incompetent idiots? [Edit: At least that the paper is garbage, as you write?] You must have gotten that really quick, without reading their references?

This is the end of the paper's discussion: "We proposed and tested a relatively new hypothesis to account for the presence of the Dark Triad as indicators of an evolved psychosocial strategy directed towards [...] We have provided a unique test, arguing and showing that those high on the Dark Triad may be characterized by cognitive biases that [..]"

I agree that the paper is likely wrong -- but I see no proof the authors are a pack of incompetent f-ckwits, as you describe them as. As I wrote, they put forward a hypothesis and tried to test it.