Indeed, in this respect, the book eats its own tail. Caplan wants to grant a presumptive authority to the consensus view of economists, but the consensus view of economists is that voters are rational, which is, of course, precisely the position he wants to convince us is wrong.
Reply: If I claimed that economists were infallible, then Hayes would be right on target. But I don't. As Hayes properly notes, I only grant economists (and other experts) the presumption of being right about their subject. And since I grant economists that presumption, the burden is on me, the dissenter, to rebut the case for the rational voter model. Hence, the book!
I should add, though, that economists' consensus on the rational voter model is only semi-serious to begin with. If you'll forgive a self-quotation:
Nearly all modern economic theories of politics begin by assuming that the typical citizen understands economics and votes accordingly — at least on average...
In stark contrast, introductory economics courses still tacitly assume that students arrive with biased beliefs, and try to set them straight, leading to better policy. Paul Samuelson famously remarked that "I don't care who writes a nation's laws — or crafts its advanced treaties — if I can write its economics textbooks." This assumes, as teachers of economics usually do, that students arrive with systematic errors.
What a striking situation: As researchers, economists do not mention systematically biased economic beliefs; as teachers, they take their existence for granted.
Bottom line: I'm not Ouroboros. On my own terms, economists can and do make mistakes. When they do, the sensible course for the critic is to assume the burden of proof and help get the consensus back on track. Which is precisely what I do.