The book's reusable? I could have sworn it disappeared for me when I used it with Scarlet...

Anyway, while it's ok that Brandon is an optional side-quest, imho, it would still be nice if he worked reliably ( wink ), which doesn't seem to be the case for everyone.
Placing one or two hints (they don't need to be too obvious) for the book in the village might be a good idea, too.