The idea of LPTHW has always seemed cool, but I've looked at the table of contents a couple of times and thought "huh, 80% of these topics seem trivial to me"; maybe I could still benefit by skimming through and reading anything that I don't already know. Also, it's kind of a bummer that there's no .mobi version.
Plus, you can't understand the solution until you encounter the problem. Reading the language manual every so often after you've encountered more problems is often enlightening. I've been working through the bash man page this way for years. (It's taking me a while because I don't really do much shell scripting, so I don't encounter very many problems that I need solutions to.)
As for .mobi version, it's a pain in the ass to generate it well enough for a "code book". It's supposed to be coming out on the Kindle store soon, but all of my previews of it just look like junk. I got it as close as I could, but .mobi just doesn't cut it when there's strictly formatted code. If you've got a suggestion on making code look nice in .mobi I'd love to hear it.