Kory Stamper’s Word by Word does for lexicography what Mary Norris’s Between You & Me does for copyediting: it makes visible the work, the worker, and the workplace.
I’ve been told of other such rules: many students come to college believing that they must never begin a sentence with and, but, or because. The it-rule though is new to me.
"I found myself yesterday realizing that I can make a little room in my life for singular they, seeing as I had already made such room without realizing it."