What is the purpose of reservations? If it is to make a caste-less society, it is not possible by your own logic (unless u force people to marry inter-caste by law). If it is to make poor people rich, then give reservation to all poor people regardless of the caste. But better then reservation in some elite institutes (IITs, IIMs) is to give lots of money and incentives for primary, secondary school education in the poorer communities and to give very low or zero interest rate loans and scholarships to poor people.