Repetition, rhythm, and annoyingness can encode messages far deeper than we expect. Yesterday a commercial from 1979 popped into in my head. Not a tagline or fragment, but the full script for a Milk Mate chocolate syrup ad, word for word. I wondered if I could possibly be remembering it as well as I felt I was. So I looked it up and watched it, saying the words just ahead of the blond-headed boy on the screen. My memory matched, 100%. Forty-seven years living rent-free somewhere in my head,...