Of course, this means outsourcing the decision back in time, too. You're basically hiring for "the best students by <questionable metric> from four years ago" the moment you factor the college into the question.
You're basically hiring for intelligence, but you're not allowed to ask about IQ, so you use bad proxies like the school someone attended.
Not 'intelligence', but 'capability'. There are plenty of intelligent-but-not-capable people out there, and plenty of capable-but-not-highly-intelligent folks as well.