@compmom, it isn’t my intent to debate semantics with you on this. “aptitude”, as normally employed in conversation, refers to talent or ability that is not acquired or developed through practice, nor is it meant to be a label for the measure of one’s achievement.
the SAT has always reflected, and still does reflect, innate ability or talent. that doesn’t make it an aptitude test. people who are naturally gifted academically will, in fact, do well on the test. but people who aren’t naturally gifted but who attend the right schools and/or who begin preparing early with good coaching will also do well. in this respect, the SAT is not, and has never been, any kind of proxy for an IQ test. you don’t prepare for an IQ test. you can, and do, prepare for the SAT.
at least that’s how it has been explained to me by those who should know. I do not profess to be an exert on the matter.
It’s like sprinting. My youngest D can run like the wind. My middle D is pretty fast for a girl who is 5’10", but cannot beat her younger sister in the 100 meters. Can’t do it. My middle D is a work horse in all that she does. Youngest is, shall we say, more cut out for the surfing world. Laid back is an understatement (and incidentally something we all love about her - she relaxes our house 
). That said, she’s faster than her hard-working sister, and nothing will ever change that. I was a sprinter myself and I know this to be true.
That athletic analogy aside, I will say this: I believe the statement people make that the SAT is a reflection of what you’ve been doing in school over the course of 3 or 4 or more years, and so in that respect, after a while a kid may be “talented” academically just because they’ve built a great academic foundation and thus appear to acquire new academic skills more easily than others. like the kid who plays a lot of sports at a high level will pick up on new athletic skills more quickly than another kid who doesn’t play as many sports at that same level. so at some point the “raw talent” and “achievement/acquired skill” line do get blurry.
this is likely the case with my middle D. I don’t know what her IQ is, but I wouldn’t be shocked if it isn’t special. she’s just been serious about her studies since she was little and has natural intellectual curiosity - always has. over the years, she’s built a formidable academic foundation, so she’s now in a position to ace IB Physics II HL - a class that kicks the crap out of a lot of the kids at her school. I’d bet there are kids who are getting a C or B- in that class this semester who have a higher IQ than my D, but at this point, who cares?
the SAT derails the academic ambitions of so many kids. I wish there were another way.