They’re saying that the only way you can keep neat and easy conversions between same-dimension units is by maintaining a lot of those deprecated units such as furlongs or chains, because by removing them, now you end up with complete nonsense conversions.
That’s not what they’re saying.
They’re saying that the only way you can keep neat and easy conversions between same-dimension units is by maintaining a lot of those deprecated units such as furlongs or chains, because by removing them, now you end up with complete nonsense conversions.