Is having two MS degrees in the same subject, from different depts, useful?
I would be very confused about why somebody needed two degrees in the same field. If the fields were overlapping but distinct—mathematics and computational science, for instance—that would not be such a big deal. But somebody with two biology degrees or two mathematics degrees from different universities would be such an exceptional case that I would want to have some explanation for this in the statement of purpose. (Why did the applicant feel it necessary to have a second bachelor's or master's degree on the same topic?)