You wrote "facilitating international migration is not very high up the list of interventions people think of. But it should be." But it would not be. Because there is no political support. People (Dani Rodrik, Alan Walters) suggested this idea before on theoretical grounds. Alan Walters proposed "Doha Visa"-- encouraging short term migration. This type of research grabs the headline and useful for discussion, but in the real world of development intervention, it is rather unfair to compare the other interventions that are really happening and on a much larger scale to one episode in New Zealand. I agree with the research and I am beneficiary of international migration. But that is an option not available to a client of a microfinance institution in Bangladesh.