Using a character to read or tell a story has been a framing device in movies plenty of times and they always have the problem of the story-teller, or the book, knowing things or saying things outside its scope of knowledge.
That looked like a standard thickness comic-book, do you really think your typical comic-book has a story in it that takes an hour and half to tell?
It's possible the comic book wasn't as detailed as the episode and retains Clark's secret identity and the identity of his family and friends. During the course of the episode we, as the audience, were made privy to stuff going on that was outside of what was being read from the book.
Again, I enjoyed this episode for what it was and seeing what little Superman stuff we got at the end was good enough for me. I just wish we got the Donner-esque shot of Superman flying over Earth at the end like in the movies.
And I'm guessing the "present day" stuff took place over a year from now since seven years from now
won't be a presidential election year.