It is important, but I think that a question is whether it should be important. That is, what is the value of a test that only, or even just primarily, evaluates how well you've prepared for it? One (or at least I) would like a test that somehow evaluated only actual knowledge / skill, so that one's score couldn't be improved by drilling. (As showerst (https://news.ycombinator.com/item?id=11067591) points out, the reason one wouldn't like drilling to improve the score is because it's the rich kids who are able to afford the time and resources to drill, and so you're testing the wrong thing entirely.)
But the SAT doesn't really go beyond basic algebra, and after getting an engineering degree, that feels burned into my ROM. I retook the GRE over a decade after my last math class, without studying, and still crushed it. Certain skills (reading quickly, parsing questions correctly, working backwards from multiple choice answers) don't leave you.
The related NYT article today suggests that all the extra english may actually make it worse for ESL students, so it's interesting to see if those goals will work at cross purposes.
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