Comment Re:LOL ... Scores of Hectares? (Score 2) 94
You're having a hard time seeing the problem here because you're familiar with the units. FWIW, what you're feeling right now (the whole, "what's the problem?" feeling), is exactly how people in the US feel about their non-metric units. I use SI every day for work, so I'm familiar with metric (and like it very much), but not with the customary metric units (which break the elegance of SI to make people feel comfortable).
The issue with the units we've been discussing is "due to the many different conversion factors". All of the factors are multiples of ten, which helps, but the nice consistency in order of magnitude is lost. For example, mass is measured in grams and masses larger or smaller than a gram can be denoted by changing the order of magnitude associated with "gram"... except if the mass is above 10^6, in which case a new unit is used without a prefix (or sometimes with one). Converting between megagrams and milligrams is easy, as metric should be. But converting between tens of thousands of tonnes and milligrams is much less elegant.
You'll keep your tonnes and hectares for the same (invalid) reasons as Americans (and sometimes Brits) will keep their odd units and no argument will convince them otherwise.