Basically (and simplifying somewhat) Kyle discusses the subject from a technical perspective while Laurie discusses the art and technique. As I noted in the review for Female Form, Laurie studied with Ansel Adams and his fingerprints can occasionally be found in her work. This book even mentions the Zone system, in the context of using the camera's histogram display. For infrared photography, where the captured images often have a restricted palette, the histogram is even more useful than in conventional photography.
There's a lot to glean from this book. Personally I find more to learn in Laurie's contributions but that's not to denigrate what Kyle wrote, just where I'm coming from with my research into the subject. What I really like is that post-processing, which is undoubtedly an essential part of digital IR, is placed in a reasonable perspective. The book leads you through the workflow of making the image with the camera and then adjusting it to match the vision. I'm particularly interested in the section on emulating the old Kodak film halation and will be exploring that before long.
Infrared Photography: Artistic Techniques for Brilliant Images by Laurie Klein and Kyle Klein is published at $37.95 by Amherst Media. I note that Amherst have really upped their game with the printing in their recent books: no complaints on that score. The format fits the usual Amherst US-Letter size, perfect bound.
I've also been sent a copy of Karen Dórame's Mastering Infrared Photography by Amherst, which I'll be looking at before long.