A couple of weeks ago I saw David Crystal give an after-dinner speech at the august annual conference of the Society of Indexers and the Society for Editors and Proofreaders. In it, he recalled having been an adviser on Lynne Truss’s radio programme about punctuation. She told him she was thinking of writing a book on the subject. He advised her not to: “Nobody buys books on punctuation.” “Three million books later,” he said, “I hate her.”