I pre-read because when I wasn’t, my response to narrations was “uh huh…. Uh huh…. Oh. Yep. Uh huh…” With pre-reading, after the narration is over, I can say “wasn’t that interesting when….?”, “What do you think he meant when he said…?”, or “Remember in (other book) when…. That reminded me of the part in (book just narrated) when…” When we read Age of Fable, there was a story similar to Romeo and Juliet. Because I pre-read it, when I haded my son the book, I said “Hey, this sounds familiar. Tell me what you think.” He read it and said “It sounds like Romeo and Juliet! Do you think Shakespeare got the idea for it from this story?”
Also, my public school education left much to be desired so pre-reading is giving me a good education as well! 🙂