More than half of the health advice Dr. Oz gives is either baseless — there’s no evidence for his claims — or wrong — there is evidence, and it contradicts what he says. Julia Belluz tells us not to be surprised:

He is, after all, in the business of entertainment.

But the thing is, there are a lot of Ozzes out there, including in areas you might not consider the entertainment business.

Recently some conference planners tried to recruit me for an event in which I would be presenting the alternative view to the main experts — Arthur Laffer and Stephen Moore. This would be the Art Laffer who among other things warned about soaring inflation and interest rates thanks to the rapid growth in the monetary base (ask the Swiss), and the Stephen Moore who was caught using fake numbers to promote state-level tax cuts.

Obviously these “experts” appeal to the political prejudices of a business audience, but taking their advice would have cost you a lot of money. So why isn’t their popularity dented by the repeated pratfalls? Are they, also, in the entertainment business?

To some extent, the answer is yes. Simon Wren-Lewis had an interesting piece on why the financial sector buys into really bad macroeconomics; he suggested that financial firms aren’t really interested in anything but very short-term forecasting, and that economists working for financial institutions spend rather more time talking to their institution’s clients than to market traders. They earn their money by telling stories that interest and impress their clients. To do that it helps if they have the same worldview as their clients.

Thinking about Dr. Oz also, I’d suggest, helps explain a related puzzle: even if you grant that the right wants alleged experts who toe the ideological line, why can’t it get guys who are at least competent? Why do they recruit and continue to employ people who can’t do basic job calculations, or read their own tables and notice that they’re making ridiculous unemployment projections, and so on?

My answer has been that anyone competent enough to avoid these mistakes would also be unreliable — he or she might at some point actually take a stand on principle, or at least balk at completely abandoning professional ethics. And I still think that’s part of the story.

But I now also suspect that the personality traits you need to be an effective entertainer on inherently not-so-much-fun subjects like health or monetary policy are inherently at odds with the traits you need to be even halfway competent. If Dr. Oz were the kind of guy who pores over medical evidence to be sure he knows what he’s talking about, he probably couldn’t project the persona that wins him such a large audience. Similarly, a hired-gun economist who actually knows how to download charts from FRED probably wouldn’t have the kind of blithe certainty in right-wing dogma his employers want.

So how do those of us who aren’t so glib respond? With ridicule, obviously. It’s not cruelty; it’s strategy.