When I was in college, a very old professor expressed the opinion that English units were better in the machine shop. One hundredth of an inch (.010) is a good unit for non-precision work and readable on a scale. One thousandth of an inch is good for precision work. One centimeter is too big for non-precision work. One millimeter (.04") is a bit big for non-precision machine work. One tenth of a millimeter is too small for non-precision but too big for precision. Anyway, I'm convinced that the metric system is a Commie plot just like fluoride in water. It's no coincidence that when they add fluoride to water, they measure it in mg/liter.