@rmaffeo I'm not convinced those citations rule out a supplementarian view. There are some passages in the Torah for which is it impossible to claim direct Mosaic authorship (e.g., Dt. 34:5-8).
It doesn't ruffle my feathers, though. It certainly doesn't change the fact that Moses is everywhere the "author" of the Pentateuch, if not in fact then in principle, in some places. He is everywhere the source of the material, even if it is perhaps, say, Joshua's pen that wrote it instead of his.
@iamjameswalters I get the point about Joshua. Clearly someone had to write the eulogy. My argument focuses on the 99.99% of the text which liberal biblical critics eviscerate with their typical anti-supernatural bent. It is such dilution of the authorship of the Pentateuch, and Daniel, and Acts, etc that helps destroy the faith of people in the pew - most of whom (in my experience) don't know 1 Chronicles from 1 Corinthians, or Joshua from Jude.
I do think, however, that you and I are on essentially the same page.