It's interesting to me that little errors like the ones you analyze in that book so often occur in books that also have much deeper flaws, like unbelievable characters, improbably plots full of holes, etc. I just reviewed a very sappy, supposedly local book, and early on the there's a description of "crab traps floating in the wintry surf." Crab traps sink, they are used in deep water or in the marsh creek, not in surf, and the crabs aren't caught in winter. And the characters and plot were just about as incorrect.