...except for writers that DO write like pynchon (e.g. DFW, Bolaño, Gaddis, Barth, though none of them would HAVE to to imitate him). Pynchon is distinctive but hardly unique.
Suppose one of those five (or others with which you are familiar) was the "actual" author of Cow Country. Who would you guess it was, based on the Amazon preview?
Honestly the preview doesn't read to me like any of them, Pynchon included. When I tried to think of a name that I wouldn't be surprised to see on the cover, the first one that came to mind was Austin Grosmman.
I am not saying that he wrote it! Just that the style of this book (based on a few pages) is much closer to his (and many other writers of his generation) than to Pynchon's.