Sorry to be argumentative, but I have been an MBA admissions consultant for many years, and and each year I get clients into HBS and Wharton - but the ones who get in to those two top programs, in particular, consistently have 720's or higher. Just my personal experience working with applicants over the course of 10+ years.
My applicants with 680's though repeatedly get into all the other Top Ten schools though, so that part is still true and valid. It's HBS and Wharton in particular that, especially in the last few years, has been skewing higher.
Telling students they can get into Wharton and HBS with a 680 and be competitive is just incorrect information...again, based on my own experience.
p.s. I am a Harvard alum.
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