I am an outsider to that whole system, but when the SAT is not coachable, then what is the purpose of schools?
For example, looking at specific question formats; learning the only topics that would be covered by tests and nothing else.
That’s all the referenced studies show.
That doesn’t mean that the SAT isn’t “coachable” with much intensive efforts, or that more minimal efforts don’t result in large improvements for some subset of test takers.