Lately I've learned to feel less bad about not reading these "policy" books. Sure, it's arguably better to read every chapter of Capital in the Twenty-First Century than look at animated gifs, but by consuming a variety of reviews, blog arguments, and interviews I can get a pretty good idea of the contents (as well as I would remember some time after reading, anyway) and also a rounded view of how the arguments were received and criticized. Mainly, I can enjoy exposure to a lot more books, and when the content-to-length ratio seems high enough I'll read it anyway.
Caplan got a lot of traction in the circles I follow, and some from a wider audience; he wished for more in Leftist Lessons of The Case Against Education. I picked this review because it gave the most complete synopsis of the book that I have seen, and was also remarkable for the way the book anticipated the objections in the review.
The wishful thinking about where Ed dollars could be better spent seems like a weak point on both sides.