Yvain has seen the misery of Haiti and India firsthand; but it seems only with his eyes.

I very specifically mentioned potential First World outlays to Third World countries as exceptions to my point. For example, I said:

There may be useful indirect actions, like advancing technology, increasing tax revenue that can be spent on useful absolute goods, and increasing the amount that flows as charity to the Third World (emphasis added)

Other than that, my entire argument was based on the "happiness follows economic growth up to a certain point, then stops" argument that has been mentioned here so many times before. That means a parable talking about how great certain interventions could be for the Third World is irrelevant; the post was very specifically and explicitly aimed at the First.

(I also think the benefits from lack of iodine deficiency are a lot less siphon-away-able)

The "60% serious" number may indeed be too high, though. I meant it to signal that I thought the argument was correct in all of its main points, but probably falls apart because the increase in productivity would produce very small benefits rather than no benefits, and "very small benefits" multiplied by the entire economy still end out pretty huge, especially if some of them end out in the Third World through the indirect methods I mentioned earlier.