I haven't read Jesus Interrupted to know. If you wanted to PM me with some examples from the book that is fine but not needed.
You are implying that all religions suffer this problem. I can believe that. But unless you know something about Christianity which I don't (quite likely )) what surprises me is how vast the discrepancy is between the Koranic Mohammad and the Hadithic Mohammad we seem to have and yet historically no one seems to have noticed it (in general).
Also go to http//www.ourbeacon.com and read some of Shabbir Ahmeds books in the Library section. There are some PDF books there that should give you some ideas about how things got corrupted.