I've had the pleasure of enduring the first five seasons and a few episodes of the sixth. He's most psychopathic in the beginning of the first season and in what few episodes I've seen of the sixth. But even at his most psychopathic, he still falls short of the real thing. If you ask me, the producers or writers intended for him to be more consistent with the books (he's much more psychopathic in the books, and the first season reflects this), but they had his character develop more emotional depth as the show progressed in order to keep viewers attached and entertained. Gotta give the people what they want...