Just as bad as his 8051 book in the quality of the English. He probably knows how to program the PIC MCUs, but I couldn't stick around long enough to find out. The book desperately needs an editor, and the publisher should be ashamed of letting a semi-literate author get away with this. It reflects on them as much as on him. The bad grammar and spelling can distract one from the technical errors. And there are plenty of those, partly oversight and partly the author's own shallow understanding.
Just opening at random to pp. 178-179, on clock oscillators I learn that "applications that require extreme accuracy allow the use of cheaper clock designs." How about "do not require"? Then I learn that "an error of 30% to the target speed are not unheard of." Sure, that's just English, but gee whiz, it's that way through the book. Then I learn that the circuit uses a "Schmidt trigger," presumably the German version of the well-known Schmitt trigger. Lower on the page I find "Crystals and ceramic resonators delay the propagation of a signal a set amount of time. This set amount is dependent on how the crystal is cut." If ever an author were asked to demonstrate that he hasn't a clue about how a crystal works, he couldn't find a better way. And so forth. It's that way on every page.
He probably knows the PIC processors pretty well, and I won't take that away from him. One pass through the book by a competent copy editor, and another by a real electronic expert could easily turn this into a much shorter, coherent, accurate, and useful book, but neither of those has happened.
All his books seem to have a strange combination of rave reviews and pans, with very little in between. That's unnatural, and the explanation that jumps to mind is bothersome.