I love to cook myself and I agree that using scales yields a more stable result (provided the ingredients are stable). But to be simpler than volume-based units

I love to cook myself and I agree that using scales yields a more stable result (provided the ingredients are stable). But to be simpler than volume-based units the scales have to be pretty sophisticated, like the modern electronic scales. Would the process be simpler if the scales could not zero-out on a weight and you'd have to weight the ingredients separately or do the math mentally? Or if they were mechanical and thus harder to read? Or if they were balance scales with pans and separate iron masses? :) Well, this is too much, perhaps, but I remember using such scales to mix solutions for photographic process. But not for cooking; this would be completely unpractical. Of course, nowadays the scales are very smart and a pleasure to use. But here's the thing: with smart equipment we don't need to bother about being metric. It's not a problem for smart scales to display the weight in any unit imaginable. I think there must be culinary apps that convert between weight- and volume-based units to suit everyone's tastes and they're either free or cost less than $5. The proponents of metric system claim it's simple. Maybe, but it's a simplicity of a typewriter compared with a modern typesetting program. Why would anyone with a smartphone care about this kind of simplicity? For example, there's ISO 216 standard for paper sizes: A0, A1, A2, etc. The sizes form an interesting progression: each size is exactly 1/2 of the larger size. But how did they select the 1st size in the row, the A0? It's pretty interesting: the A0 size is exactly 1 square meter. I bet the designers of the standard though it would be be a feature, because the users (e.g. printers) will be able to use this fact to simplify their calculations; e.g. you need to print 1000 A4, you know it's 1/16 of A0 and the paper is 100g/sq.m., and you go from there. But I don't believe anyone does this kind of math nowadays; everyone has computers and printer jobs have much more variations in paper sizes and densities for this "simple" rule to be of practical use.