I'm really interested in this topic. We have always had a metric system, and for us was very difficult to understand yours
. We can discuss about what system is better, but I think that the real important matter is to understand what we are doing. Lbs and Kgs are about one the double of the other, so it's easy. Something more difficulties can be found in minor measures.
For us, with decimal system, everyting is counted about 10. 1Kg=1000 grms =10 hgs =10 x 100 grms, and so on. We divide for ten, for five or for two.
1/2 kg, 1/2 hg, and so on.
I remember that a lb was about 450 g, a onze about 30, and....I don't know nothing more
. But I have never thought to temperature. For us, water is boiling at 100°. And frozen at 0°.
I remember some years ago, examining some drawings coming from Malaysia: we had a lot of problems in converting them in our measures, until we realized that the scale was not 1:100, but something similar to 1:98, according to dimension of yards.....