The American League believes in comparative advantage, and has a designated hitter bat for the pitcher. I prefer this: I believe in comparative advantage and division of labor (and being a White Sox fan from age 5, I like the American League anyway).
This afternoon we heard a performance of Pagliacci, before which an announcer informed the audience that the soprano was ill, but would act the role while another—the designated soprano—sang from the side of the stage. The acting was better than usual, and so was the singing—an illustration here of comparative advantage. The overall effect wasn’t good: Opera is both acting and singing, and it was absurd and disconcerting to separate them. The production function for opera requires one person doing both—division of labor makes no sense in this case.
(HT to FWH)