I'm no expert on American university admissions but this cannot be true -- most people applying to study in America will have applied to more than one university and this could really only be true if almost all of them only got one offer. Otherwise I don't see how this could work. Say somebody gets offers from two universities in America; they clearly cannot attend both institutions so it seems unlikely that this rule exists. It just wouldn't work. Not to mention I'm aware of people who've had more than one offer and have turned down all but one.(Original post by Rabadon)
The issue is that if you apply to american unis in the first admissions cycle, and they accept you, you have to go. So american uni deadline for reply is december 15th, so if he is accepted by then and he has an offer from cambridge, has must go to the american uni.
I also suspect that the 15 December reply is for early applications because I seem to recall that at least the Ivy League lets applicants know of whether they were successful in April, not December.
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