Light verse, for some reason, demands to be written in a rather old-fashioned way. The language can, and should, be as modern as you like, but it should still not merely scan and rhyme, but should do so with felicitous ingenuity. It should pour itself, without any contortions, into apparently complex molds. There is an enormous satisfaction in reading what could be, say, an extract from a legal document, full of whereases and notwithstandings, which the poet has contrived to arrange into triple-rhyming decasyllabic quatrains, with the odd internal rhyme for the hell of it.

This was the sort of thing that Wodehouse liked, together with the typical frills of English light verse, such as the sudden letdown from mock-romance to slang. He liked the idea of an established form being made to learn new tricks. He liked the unbuttoned, conversational style, moving within strict measures. (His novels...