Currently, when you're on the Recipe section of your Bookshelf, you can select to just see recipes with a certian bookmark either on the Book level or on the Recipe level, but not both at the same time. To me, it would be useful to be able to search for recipes tagged with a certain bookmark, within a group of books tagged with a certain bookmark. If you don't need to refine either the Recipe level or the Book level with a bookmark, you could just not select anything in that dropdown.
I wonder what you guys think?