The Moral Quandary of Commas

Early on in Dreyer’s English — the bossy style guide of Random House’s copy chief — Dreyer tells a gossipy story about a fancy garden party at the Upper East Side townhouse of an unnamed novelist and her famous husband, a director. There he meets the Tony Award–winning Australian actor Zoe Caldwell, who complains to Dreyer about the copy editor who bedaubed the manuscript of her memoir with “scrawls and symbols.” At first she was baffled, she tells Dreyer, but slowly she came to an epiphany. “Copy editors,” she explains, “are like priests, safeguarding their faith.” Dreyer predictably swells with pride, taking Caldwell’s observation as a “benediction,” a r­eligious blessing of his editorial craft.

Like all good anecdotes, this one is revealing, though perhaps not in the way that the author imagines. Although most decisions about writing “can be addressed only on a case-by-case basis,” as he himself concedes, Dreyer at times can be...