My point is that when someone says “the biggest differentiator between the students who scale up quickly and those who scale up a bit more slowly is their aptitude for memorization....” this is a mis-interpretation of the evidence that the “quicker-scaling” students remember facts they read more readily. What actually distinguishes these students is fluency in comprehending and associating material conveyed in writing/speech. Which may vary slightly based on inherent traits but comes down substantially to cumulative past practice listening/reading to complicated language. By high school students have more than a decade of practice, and between the most prepared and least prepared students there is probably something like 10x difference in amount and quality of past practice, most of it outside of school. Some students are barely reading the few assigned novels and textbooks while others are reading multiple (extra-curricular) difficult books per week on a variety of subjects and having extracurricular conversations where they construct and parse complicated arguments, etc. The latter group have a huge advantage.

Students’ skill at specifically remembering lists of atomized trivia (what people often mean when they say “aptitude for memorization”) is not as important, though this is also a trainable skill for anyone who really wants to do it.

Similarly, between the kids who play sports or do other physical activities all the time and have some amount of expert coaching and the kids who only play sports in PE class, there is probably something like a 10x difference in cumulative quantity/quality of past practice. Which ends up making it seem that some students are “athletic” and others aren’t.

And similarly for music, electronics, carpentry, abstract mathematics, cooking, shooter games, or whatever other skills you look at.