I've seen it written both ways. What's the difference between a "Hypothesis" and a "theory", anyway?
I have as well, but it is usually called the "theory" as a means to mitigate its validity. A "theory" sounds less systematic and scholarly than "hypothesis."
The JEDP is extremely complex; so much so that I doubt there is one single publication that covers every aspect of it, pro and con.
I don't know of any scholar, even conservatives, who believes every word of Deuteronomy was written by Moses. I mean come on, the book contains his own obituary and refers to Moses as the greatest prophet ever. Hardly sounds like something he would or could have written.