You'd have to put an unusually high value on air cleanliness to argue that oil, period, and the scale economies it has enabled, has not have a net ROI in total.

You'd have to put an unusually high value on air cleanliness to argue that oil, period, and the scale economies it has enabled, has not have a net ROI in total. Whether the marginal added "value" to some, of commuting in a hummer vs a Prius, is worth the cost to third parties of the incremental added pollution is, of course, a different matter.