Last night, I realized that not every one uses standard tools to measure anything. I am attending a series of lectures in costuming this weekend. All aspects of making costumes both historical and fantastical. This is interesting because everybody's body is different and most of us are not truly symmetrical.
If you were to buy a pattern, on the back, there is a printed table telling how much material you need to buy to complete the pattern. Anyone who sews knows these are "guidelines" not set in stone because depending on the type of material, the pattern, contrasts, etc you can often get away with less materials.
But what if you did not have the standard rulers, yardsticks and such? How do you measure things? Well in many native cultures, they insist on using thumbs, fingers, nose to fingertips, etc to measure anything. The logic is that everyone is different and if you use your own body to measure things, then the outfit produced will fit your body in the correct proportions.
Interesting idea! Perhaps when teaching proportions, we can take time to discuss this idea to show how it works in a real life application that uses the idea without using all the numbers. I need to give that some through.