I've never read a book in an attempt to find a philosophy for myself, I read all of her work when I was in my early/mid teens, and her views match mine quite closely. I appear to be very cold to most people, though, so I shouldn't be surprised.
I don't think of Stephen Shore as a documentary photographer, although I think our difference of intention with syntax, and meaning is what's causing us to see differently. I think of documentary photography as something much more closely related to photojournalism, with the intention of 'documenting' an ongoing, reoccurring subject. I agree completely with you that there is an overload of "documentary" photography that consists of mediocre landscapes of Americana, and smushed out cigarettes. That's what you get when everyone is told that they can be a photographer, too (Just add water!).