Sure. There just isn't a way Tarquin can not be a deficit to any happy ending, although fortunately (...or unfortunately, depending on one's point of view) the happy ending question was only about This Story, not about Elan's life. You believe differently because (let me know if I'm paraphrasing you incorrectly) you consider the fact that Elan has a plan which he believes will deal with the problem of his father in some morally satisfying way to trump any in-comic evidence of Tarquin's irredeemability. I don't; I consider the in-comic evidence overwhelming and "Elan thinks he can do it" to carry little or no weight. We'll find out who is right when Rich's thumb is better.Because I think that would be a display of shallow morality on Elan's part.