Hello,
MBA Connect shows all those who are offered a spot, it can be done in 2 minutes, and it is private, the other schools you apply to will never know whether you are registered or not. I think 99,5% of those who have an offer do so : even if you really want to go to MIT, it would be quite dumb not to register to MBA connect and check out what goes on there for 20 min. The only binding process is when you deposit your non-refundable €€€€. Some of the people there will chose another school, so after the payment deadline, the list will be cleaned to show only those who are committed to go to insead. In a month, there will be fewer people listed.
About the diversity, I am sure they manage it intake by intake and not year by year. Their goal seems, for each intake, to offer the best ratio quality/diversity they can have. This goes not only for nationalities but also for past experience, education, age, etc. However, they insist that the number of admits is in relation with the number of applications, in order to keep the game fair: they may admit 55 indians, but they won´t admit 55 swiss, because the application pool from Switzerland is limited (or i guess so
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