Well, first of all, we did lots of studies where we show practical intelligence doesn't correlate with G. We have probably two dozen studies that practical intelligence better predicts job success than IQ.

There is no recipe to be a great teacher, that's what is unique about them.

In other words, if a teacher only teaches in one way, then they conclude that the kids who can't learn well that way don't have the ability, when, in fact, it may be that the way the teacher's teaching is not a particularly good match to the way those kids learn.

So, for example, if a child is labeled as having a learning disability, it has very concrete consequences for the kinds of services and potentially accommodations that child will get.

ACT and SAT each have their own parts of the country. The GRE has its lock on graduate admissions. And so, one could blame the companies, but really, economically, they have no incentive to change things very much because they're getting the business.