alexmacphee
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This is the great and often overlooked practical advantage of Imperial measure. I've lost count of the number of times I've come across a recipe that's called for 910gm flour, 55gm sugar, or whatever, recipe amounts that are clearly taken from Imperial values and just converted. The great thing about pounds being sixteen ounces is that you can repeatedly halve them and still have nice integer numbers to deal with, right down to an ounce being sixteen drams. Ideal for recipes because so often you need to halve things or double them up. Sure, the scheme breaks down a little when you get to fourteen pounds in a stone and so on, but on the whole, the practical value is higher of manipulating twos and threes instead of hundreds.
Metric makes it easy to calculate very large and very small numbers, that's the primary advantage. There's an old rule of thumb about using the 'right' unit for approximation purposes and rounding. So when you talk about a length of 'about 15 inches', you can expect the value to be in the range 14.5 to 15.5. You wouldn't give the distance to the Moon in inches, since this would have an implied accuracy of +/- 0.5 in. A recipe calling for 910gm implies an accuracy of +/- 0.5gm (though in practice nobody would would bother with that level of precision). I quite often see recipes with dry ingredients listed in grams, and liquid ingredients in fluid ounces or parts of a pint. (Fortunately, not developer recipes.)