For the first decade I read, and re-read Charlie P's books religiously...and then, as my experience mounted, I didn't use the book at all. I eventually moved on to Daniels' Designing Great Beers, and then I think that info got a little stale (in the second decade), and desperately needs an update. I recently got a copy of Palmer's book as a gift, and I couldn't stay focused....it isn't that it isn't good info, but still pretty basic. I am sure there are nuggets in there, but I lose interest. I feel like I am half way between the two in my philosophy anyway(that is what brewing is, ultimately, philosophy on a bunch of a priori and a posteriori prepositions). There is also the battle between the art and science, the free form movement of American Homebrewing and the BJCP style guide, but it is changing so fast, a regularly published book can not keep up with all of us, though I wish it could. The internet and this forum works wonders, however.
I still have my original copy of The New Complete Joy....I should try to read it again....but fear the worst.