The factor argument is not really something that stands up, because you need to consider factors for an arbitrary length of something in the world, not a well d

The factor argument is not really something that stands up, because you need to consider factors for an arbitrary length of something in the world, not a well defined unit of your own making. How about 1/3rd of a tree? It's likely to be in some ungodly fractional amount of an inch, that's extremely hard to convert into feet, but in metric the decimal system just makes it super easy.