> By the time you've read the explanation, you've moved past it
Not with dense material. Often, I'll read through a chapter quickly, then go through the derivation of something three or four times until I understand it deeply, then re-read the chapter again once or twice to fully grasp it (at which point the derivation is just taking up space and I want to understand the grander scheme). Granted, I'm applying my approach to upper-division to grad-level physics textbooks, but that's the extreme I'm personally hoping to make more approachable for people.
Not with dense material. Often, I'll read through a chapter quickly, then go through the derivation of something three or four times until I understand it deeply, then re-read the chapter again once or twice to fully grasp it (at which point the derivation is just taking up space and I want to understand the grander scheme). Granted, I'm applying my approach to upper-division to grad-level physics textbooks, but that's the extreme I'm personally hoping to make more approachable for people.