so you're saying this:
is easier and makes more sense than this:
sorry, but no.
oh and fyi: germany sells their tvs in inches (zoll) because the international production standard for tvs is inches. (they also show cm on ads) why? because the first tvs where produced and advertised in inches.
so if you're saying a foot is always a foot but two people have two different shoe sizes, e.g. 8 and 12, how can they meassure the same thing? they still have to know the mandatory, actual length.
just watch this video. https://www.youtube.com/watch?v=r7x-RGfd0Yk