Yup, and it's probably convex - something like 1 + 1 + 3 = 5, but 3 + 3 + 3 > 12. That would also explain concentration of tech in a single area, or a few areas

Yup, and it's probably convex - something like 1 + 1 + 3 = 5, but 3 + 3 + 3 > 12. That would also explain concentration of tech in a single area, or a few areas of the world.