Tiller had just walked through Clark Stanley's 19th-century snake-oil act — the infirm man with the walking stick who leaps up cured after a rubdown — to show that the anecdote, the emotive language and the bait and switch have not changed in a century. This is his explanation for why the pitch stays frozen while science keeps moving. The practical payoff, he argues, is that learning the pattern once inoculates you against the next thousand versions of it.