Thanks for a good post, with lots to think about, including traction for 'policy equipoise'. I do have an immediate question. On this point (and with Jeff Hammer's recent comments about 'our' ability to answer questions about opportunity-cost (in Lahore) in mind), 'The question is not “does it work” but rather “should public resources be utilized in this way at the expense of alternative uses'?"... This strikes me as an argument for testing 2 interventions (or variations on one) against each other rather than leave-out(?).