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Raj, I really appreciate your thoughtful comment because it cuts to the heart of the issue. I would like to illustrate the question you raise with an analogy. Suppose a group of people generally takes aspirin for headaches. We start a program to get them to take Tylenol instead. Part of the group is encouraged to take Tylenol for headaches and does so; the rest of the group keeps doing what they were doing before: taking aspirin for headaches. What is the 'effect' of what we're doing? There are two ways to define it. If you want to know the impact *of Tylenol*, you would want to compare pain in people who took Tylenol to pain in people who took nothing. You might find that Tylenol cures headaches, and works "exactly as advertised", in the words of the MVP. If you want to know the impact *of our intervention*, you would want to compare pain in the people we encouraged to take Tylenol to pain in people who kept doing whatever they were doing before we came along---taking aspirin. You might find that there's no difference in pain between the two groups, because both Tylenol and aspirin reduce pain effectively. Thus the effect *of our intervention* on pain is nil, even though Tylenol works "exactly as advertised" to reduce pain. Thus we have two different questions and two different answers. One is not "obviously" more correct than the other. But in the context of the MVP, one is much more useful than the other. There is no doubt that fertilizer raises crop yields. That is well established. We do not need an evaluation of that. There *is* important doubt about whether the MVP causes crop yields to go up more than they would have gone up due to whatever would have happened without the MVP. Going back to the analogy: We know Tylenol works, so the first form of the question is not useful to pose. We don't know whether our particular Tylenol promotion campaign makes people have less pain; that *does* need evaluation. We are extremely clear at every point in our paper that we seek to measure the impact *of the project, as a project*. So I am baffled by the MVP's immutable confusion on this straightforward point.