I'm an instructor/accidental ID, moving into my first fully ID role. Picked up this book for some tips. I don't know if this just hasn't aged well (revised edition from 6 years ago), if my skills are already beyond this book, or if I just don't like the visual style presented here.
The nutshell version of this book is: use PPT for things it isn't designed to do, and it's ok if everything is ugly. I'd rather use a proper tool and have the visuals not be distractingly poor. It does present a solution (of sorts) for situations where you're the only ID, you only have PPT, and you absolutely must design interactive branching storylines.
Ultimately, I didn't gain anything useful from this book. But it did remind me that I want to learn more about PPT master slides. I've used and created them before, but there's probably some depth I'm missing, so I should look into it more.