I don't mean they're close enough to be interchangeable, just that they're close enough that it's dumb to have separate scales. They're useful for having peopl

I don't mean they're close enough to be interchangeable, just that they're close enough that it's dumb to have separate scales. They're useful for having people understand speeds at different scales, but only because the different scales of units line up stupidly. Of course the effort to change it isn't worth it, it just makes you wish we'd got it right the first time around.