PS: I tried to use a saved story item in a book. It appears as another item that can be added to a book. Unfortunately the programers of FTM did not take this the one step further to make it very useful.
If they had made it such that when opened the book imported the story item, it would have made it so that you could edit the story item and it would all ways be current when ever you opened a book that that story item was used.
Unfortunately they choice to import the story item in the book and incorporate into the book. Doing it this way creates a second story item that must be edited in each book if you want the story item changed.