It seems to me if everybody uses very poor tests and they're all the same, then it's very harmful to society. But if everybody uses different, uncorrelated, ver

It seems to me if everybody uses very poor tests and they're all the same, then it's very harmful to society. But if everybody uses different, uncorrelated, very poor tests, then people who have talent generally end up somewhere and there may not be a lot of benefit to improving the tests. In fact, improving the tests could lead to more correlation and excluding/wasting more talent.