[olfactory]

Maybe different learning styles? I spoke with one very young math prodigy a few years ago who told me that her secret to self teaching advanced material was that she tries several texts and ends up using the one that teaches the material in the way that she finds most intuitive.

[fjsolwmv]

People say that but usually the truth is the second or third book is the "best" (regardless of which book) but really it's because the material sinks in after multiple itersations, other worse because the material feels familiar even though the student hasn't actually learned to solve problems, they've just memorized bits.

[bytematic]

So how would you solve that problem in a centralized system? I don't think "reread this section 2-3times" would necessary work.