> But not everybody built like that, there are also many examples of elegance and material economy. Roman stuff spans the gamut from 'wasteful' to 'optimal'. A

> But not everybody built like that, there are also many examples of elegance and material economy. Roman stuff spans the gamut from 'wasteful' to 'optimal'. And note the survivorship bias. The stuff that was "not quite enough strength to be sufficient"-- or even "just barely sufficient" was removed by time.