The biggest problem with education is that who the kid is(smart, hard working, resilient) has 20x the impact of his education. So it's much easier to select 5%

The biggest problem with education is that who the kid is(smart, hard working, resilient) has 20x the impact of his education. So it's much easier to select 5% better students than it is to teach them 100% better. And if teams of phd researchers are arguing over whether colleges in general are signalling versus human capital, how are some random parents going to be to solve the much harder problem of if a single school's results are due to signalling or human capital with less time, training, and information?