The Undercover Economist Discovers Rational Blowjobs?

Arnold Kling writes;

Is called The Logic of Life. I hated the introduction. At one point, Harford writes,

Might there not be such a thing as a rational blowjob?

I don't think of myself as a prude, but I wound up muttering to myself about economists who think that sex is a good choice for a topic. Might there not be such a thing as diminishing returns and comparative advantage? I want the next pop economics book to be entitled The Undercover Economist Discovers that No More Sex Equals Safer Freakonomics.

Maybe the issue has more to do with the difference in cultures of British and American writers.