When someone tells me "half a kilometer" assuming they really mean 500m would usually be a dreadful mistake. It means "some uncertain distance you can probably walk". Decimal units don't magically make people more accurate.
When someone says "half a quart" who the fuck knows how much that is? I sure don't, and I'm American. Hell, even a regular quart throws me, all I have there is a vague notion that milk is sold in that amount. When someone says "half a liter" you can be sure they mean 500ml, and you can instantly know how much that is in any kitchen measuring device you have.
Suppose I am recounting a dish I made to someone over the phone in two realities, one with Imperial and the other with metric.
Imperial universe: "Okay, now add... say... a third of a gallon of milk" "...third of a gallon.. eehh.. half a pint of milk.
Metric universe: "Okay, now add... say... 2/3rds of a liter." "Two thirds of a liter... 666 ml it is then."
In the imperial universe poor conversations force two inaccurate estimations. In the metric universe only one of the parties is being dreadfully inaccurate.
Imperial is defined in terms of metric units, so it is possible to be as accurate in imperial. The difference between imperial and metric is that imperial adds mental overhead that in practice reduces accuracy.
One third quart = 2/3 cup. I have a 2/3 measuring cup in my kitchen.
I've never heard anyone say a third gallon, but just convert to ounces. 128 / 3 = 48. That's 3 pints, btw.
Of all the "math is hard" arguments, I think the kitchen measures are the least convincing. Everything is a power of two. You can halve or double a recipe without even thinking.
All of these conversations, even with special cases already marked on kitchen equipment, are all more complicated than the stupidly simple equivalents. Why in the world would you choose imperial over metric, unless you are just an old curmudgeon?
You can think the arguments for metric are weak (most of the world disagrees...), but the arguments against it are nonexistent.
(Dividing by two is just easy in a decimal numbering system as it is in a hybridized decimal system, so give me a break)
The cost of switching is non zero. I'm not bothered by metric, I can deal with it just fine. I'm just not bothered by standard units. I would never propose switching to standard from metric, but I just don't see what all the fuss is about.
Switching would be done in a lazy manner. I can't see how the cost would be prohibitive, plenty of other countries have managed it so surely America can too.
