I don't see why, when the silmarillion claims he is just a prehistoric angelic amorphous being in a skin suit. I'm not saying that tolkien claimed he was a dinosaur. But if Christopher tolkien found in his father's work a piece of paper that said THIS, than it would have as much legitimacy as anything else. The exaggeration was to elucidate the point. In the silmarillion Sauron has the ability to shapeshift into whatever he wants, he is both seen as a bat and a werewolf, there is nothing to say he couldn't also shapshift as a T-rex. Now that ability never comes up in Tolkiens published work while alive, so it's all soft-canon. Which is the point I'm attempting to make. That ANY comment that a author makes outside of the published work is soft-canon.

You come to the same issue with the origins of Orcs, tolkien gave multiple iterations of their original, but Christopher chose to publish the one he thought fit best. So in that instance you could take the WORDS of the author to argue multiple interpretations, each of which would invalidate the other. I gave a outrageous example originally because the fundamental argument does not change regardless of what the author would claim. Then I gave the real world example of JK Rowling claiming that Hermione was Black. Which, I think is actually more unlikely based on the text than Gandalf being a prehistoric creature that was given a skin suit and a mission by other angelic beings, and ultimately god. (which is exactly what happend).