That reminds me of an article, perhaps in the late 1960s, in QST by John Troster, w6ISQ, author of all manner of joke articles. The title was something along the lines of ?Murphy?s laws of electronics?. One of them: ?A transistor, protected by a fast acting fuse, will protect the fuse by blowing first?. Another one: ?A dropped tool will land where it does the most expensive damage ? this is know as the Law of Selective Gravitation?. (That came with a cartoon showing a hammer nudged off a shelf, on a direct path to an expensive vacuum tube in an open chassis on the bench.)