Imperial is more "humanly" practical...
- For inches to feet, 12 is a really nice number. You can halve it, quarter it and third it. With base 10, you have a hard time with thirds -- and even quarters are not integers. Such measures are better for building.
- Miles are 8 furlongs (a furlong being the amount of distance an ox could plow before taking a rest), and the mile is also roughly equivalent to a roman measurement of 1000 paces -- that's a nice way to think about how far you should walk before taking a sip from your canteen. Sorry, but kilometers don't do it for me.
Imperial is simple for a human being to "visualize"...
- Inches are about a thumb-width -- it's a nice physical measure, and a nice rule of thumb.
- There are about 4 inches in a hand -- which is roughly knuckle to knuckle.
- There are three hands to a foot.
- The measure of a man's arm from fingertip to elbow is approximately a foot and a half -- a measure also known as a cubit.
- Yards of cloth in stores used to be commonly measured by hand -- by stretching out the cloth an arm-width away from the center of the body... When I was young I saw women at the cash register measuring out cloth by hand -- it was common-place.
- Teaspoons are teaspoons -- is there an convenient equivalent measure in metric for a sip of something?
- Tablespoons are tablespoons -- same again as teaspoons... Is there a ready replacement even on metric kitchen tables?
Imperial is better on the human stomach.
- A cup is a nice amount for your coffee. I don't want to ask for 225ml (or whatever) measure of coffee -- I want my darned cup.
- A pint and a quart are really nice measures for beer in the tummy. I DON'T WANT a Liter of beer. I want to "mind my pints and quarts."
- An ounce is a nice shot of liquor. I know three of them will put me down for the night.