I partly think that maybe the marketing folks just aren't in touch enough to understand why they're wrong. That's not so much their fault as much as it is mine for not pitching the concept in terms they would understand. The book is essentially an end-to-end case study book that follows the development of a product from idea to publication, including requirements, design, how to do test-driven development and solutions to at least a half-dozen problems that you encounter in practically every app.
Oh well... I'll keep pitching to other publishers and she what happens. One way or another, I'm going to get it "out there" even if I have to publish it myself. It's a natural next step to my first book.