Re-reading feels productive and barely works
Why re-reading fails
Familiarity is mistaken for knowledge. The text feels easy because you have seen it, not because you could produce it.
What works
Close the book and write down everything you can remember. Then check. The gap you find is exactly what to study next.
Spacing
Revisit after a day, then three days, then a week. Spacing is uncomfortable because you forget between sessions, and forgetting is what makes it work.
