To be honest I regularly convert between units. Especially mm, cm and m (sometimes km) and liters to kg. And g and kg. So I dont really understand how that isnt neccessary for the majorjty of America. Does noone build stuff, or I dont know, put a picture up a Wall, stuff like that? I know you said it is easy to half stuff in imperial. I dont really half stuff that often? When measuring stuff I mostly add, subtract etc. I very rarely just take 50% off whatever I measure. What do you do to need so much halfing stuff? If I need rope I want a specific length of rope not half the rope that is on the wall.