The evidence says that SAT prep courses do not make much of a difference:

"From 1981 to 1990, three separate analyses of all the prior studies were published in peer-reviewed journals. They found a coaching effect of 9 to 25 points on the SAT Verbal and of 15 to 25 points on the SAT Math. In 2004, Derek Briggs, using the National Education Longitudinal Study of 1988, found effects of 3 to 20 points for the SAT Verbal and 10 to 28 points for the SAT Math. Donald Powers and Donald Rock, using a nationally representative sample of students who took the SAT after its revisions in the mid-1990s, found an average coaching effect of 6 to 12 points on the SAT Verbal and 13 to 18 points on the SAT Math. Many studies tell nearly identical stories. On average, coaching raises scores by no more than a few dozen points, enough to sway college admissions in exceedingly few cases."

(from https://www.aei.org/articles/abolish-the-sat-2)

Most people scoring 700+ on SAT-M experience no time pressure on the test. (That could be read as tautological, but I’m fairly convinced that there is no real time pressure that would dramatically shift the “SMPY/SET eligible” from not. The questions are straightforward and there’s more than ample time provided for those with a realistic chance of scoring 700+.)

The extent of my tutoring was a public school guidance counselor explaining to our whole class who was taking the test that there was statistically no penalty for guessing and how the “A is greater, B is greater, C means equal, D means indeterminate” questions worked. That was 30 minutes at most.

My high school did intense drilling for SATs as an after school thing. The average kid in my class had a 180 point improvement versus the PSAT as a result.

High SAT scores are evidence of high SAT score.

I got a 760 on SAT-M and I definitely felt tremendous time pressure. I am convinced I could have gotten 800 with no time limit. At the same time someone much smarter than me could probably get an 800 with half the time given.

> I also realized that SAT scores are heavily impacted by SAT specific training/tutoring

It's difficult to realize something that isn't true. The effects of training on SAT scores have always been negligible, less than the measurement error associated with taking the test one time.

When I was tested in that first cohort, I received no coaching whatsoever. I was 12 years old.

ah yes, the exorbitant cost of $35 for an SAT prep textbook

Well, even better, you don’t even need to purchase them—most public libraries have SAT prep books available for borrowing.

When I was in high school, I would check out whichever ones were available at the time and would photocopy the whole book. I drilled myself on the tests until I scored 1600s every time. Shows how flawed they are as a testing vehicle.

That's not evidence the tests are flawed. I was just having a very similar conversation with a friend who aced the physics olympiad. She said, "it's too easy to game, all I had to do was try old tests on my own". Well, hundreds to thousands of others were putting in more hours doing the same thing, in addition to enrolling in expensive prep programs, and they didn't do as well as her.

That is evidence in favor of the test's quality, not against it. There's no paying to win.

That’s a good point. You’re right if the aim of the test is to measure information retention, and not raw intelligence.

Never mind what it measures. My main point is that whatever it is, it's not simply "dollars spent on prep". Good tests provide an opening for the less well-off to succeed, despite the more well-off doing everything they can to rig it in their favor. My parents (and by extension me) owe a lot to them.