i think the principles you lay out make sense. And in the evaluations we do in these contexts, these are things we strive for. In addition, one of the points that came up in the workshop (where the particular context was therapy for surviors of violence) was that the control group didn't get nothing -- they got a different type of therapy (and it was clear ex ante which one dominated). My guess is that this is likely a common course of action where you are in post-conflict settings and resources are not constrained.
However, I would like to hear more about this -- so if anyone has examples of how they handled this please do email me and I can do a later post that does a better job of answering Vivek's question.