Just about a month ago I realized for the first time that legacy admissions result, in many cases, in better candidates rather than worse. Not always. But here's an example (from real life, without names obviously): highly qualified student, with lots of national level achievements, Cornell legacy. Applied in the early admission period to Cornell, got in. But the student had a reasonably high chance for Princeton or Yale, let's say. However, the legacy system incentivized him to apply to Cornell, even if his level was slightly higher. Why? Because if he didn't apply in the early period to Cornell, hoping for Princeton or Yale, and didn't get in, then Cornell would not have given him any preference in regular admissions. So he had to choose between nearly 100% admission at Cornell in the early round, vs 10% chance at Princeton, and then a non-negligible chance to not get into Cornell in regular.

My point: legacies are not always dumber than non-legacies. Sometimes they are stronger, and the legacy system incentivizes them to stick to the school where they are legacy.

Which kind of student do you think would be more likely to realize that a single data point is of no consequence: legacy or non-legacy?