"Really, you seem kind of sickly to me." Well, scrawny with a cough which wasn't really the same thing, but Stein had sensed he was pushing a button and figured he might as well go all the way. For fun, of course.

He blew out a stream of smoke as though to accentuate his point. See, he was healthy enough to chain smoke and not cough constantly. Clearly science had given him an advantage.