30 years ago trying to get us to go metric was like hiring a Chinese guy to teach us to speak Spanish... How could we learn metrics with no metric measurement tools readily available? Computers were new and there was no google to figure it out. And who knew enough about metrics to teach us?

Then, and now, I could care less about metrics. I've been forced to use metric measurements because my Chinese built laser engraver's software has no 'inches' option. And after 2-1/2 years, about all I've learned is, 1mm is just shy of .040, 3mm is almost 1/8", 6mm is almost 1/4", 100mm is around 4"... So I have 1 to 4 inches "about" dialed in... but the other day on the boat board, there was talk of a damaged 157cm diameter propeller was being fixed-- so pop quiz, how big is 157cm? oh, right-- 1570mm, how dumb of me... But seriously, I have absolutely NO idea how to picture IN MY MIND what 157cm is, no clue whatsoever. Google tells me it's 61.8", or 5' 1-3/4", which BOOM!! my brain can immediately relate to! That's how tall my mom was! Just a little shorter than I am! And that's pretty big for a boat prop!

--but 157cm means no more to me than la taille est que?
(which I also had to look up)

I'm fine leaving well enough alone. Last thing I ever want to ask for is a 305 hot dog...