I think it's easier to get a tiny fraction of the planet to do a complex right thing than to get 99.9% of a planet to do a simpler right thing, especially if 99.9% compliance may not be enough and 99.999% compliance may be required instead.
This calls for a calculation. How hard creating an FAI would have to be to have this inequality reversed?
r/Fitness does a weekly "Moronic Monday", a judgment-free thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. I thought this seemed like a useful thing to have here - after all, the concepts discussed on LessWrong are probably at least a little harder to grasp than those of weightlifting. Plus, I have a few stupid questions of my own, so it doesn't seem unreasonable that other people might as well.