If Mike Huckabee had proposed a completely different tax plan that has one point of similarity with the idiotic, doesn’t-add-up, Scientologist-designed “FairTax” plan he actually proposed, then that completely different plan, with its key details still to be determined, might be a good idea. So it is unfair to criticize him for offering the plan he actually offered.
As a sorta-kinda economist myself, I deeply resent the fact that many Slate readers probably think that Landsburg’s stuff represents the way actual economists think, rather than being more finger exercises in vaguely economic reasoning: sometimes amusing, often disgustingly heartless and wrong-headed, never intellectually or morally serious.