John McIntyre, formerly a top copy editor at the Baltimore Sun, and a loser in the downsizing panic, writes about a book he’s just read:
I also note, with professional regret, the numerous typographical errors throughout the book, many of which have been corrected by a previous library patron. Apparently I am not alone in finding them irritating.
I used to do that, but then I felt bad about defacing library books. Can one deface that which is already defaced by error? At least, there is someone else who appreciates the impulse.