Reading thru this thread, it dawns on me that some of our brains work quiet differently.
I do not read as much as I used to...partly because of several years of vision problems which made it hard to focus at one distance. But I still have lists of books I try to re-read whenever possible.....and I find that, although I 'know' some aspects of the plot, I do not always remember "how it comes out" or even exactly how major twists & turns develop. It is very much like reading a story that was described to me at one time.
As many of you know, I am a woodturner, and I had much the same issue in making certain design features in things like lidded jars as I do in reading.....I didn't 'remember' exactly how I had proceeded thru steps. (After numerous repetitions of the same procedure, I can then remember & describe it pretty well.) Thus, my display at a show is always different as I seem to have difficulty making 'the same thing twice'. (Of course, over time, there ARE very close repetitions, as certain forms are almost automatic).
I seem to remember general conceptual formats and that I LIKED certain books....and can remember titles and authors and can even quote paragraphs from some....but rereading a book is 'almost' like reading it for the first time. I simply do not always know who is going to do what or what the final outcome will be.

(I have the same problem with my life in general...I have difficulty remembering what events came in what order... or the dates. I know people who mentally catalog it all as if taking noted for a biography. Me? I just rerun little movies of items of interest and have to sit down and WORK to calculate exactly when they happened.)

I'm just beginning to re-read Isaac Asimov's "Foundation" series, and am quite curious to see how it all develops... ☺.