I wonder if EA could ever be implemented in a way that proves or disproves it as a viable strategy? It seems to me that the inherent problem is that people will always behave in subtle and not-subtle self-interested ways that make "true" altruistic behavior devilishly difficult to carry out in the real world (especially under the conditions that arise granting you the billions to carry the philosophy out). And therefore almost impossible to falsify.
Sort of reminds me of the old adage, "Communism cannot fail, it can only be failed." With some people today exclaiming that true Marxism has never been tried. But I can't imagine what perfect conditions could exist that would allow either communism or EA to be carried out, without having to account for human nature in the end.