[Galin]

The overlap with Q&E proper might (arguably) lend a certain measure of 'validity' to the actual tale itself; but that said, I think the 'caveat' (of sorts) is still to be noted. In any case I don't feel I can tell this or that person how much he or she can rely on all the details in Cuivienyarna as 'true history'.

For me the Fairytale creates no difficulty even if 'true' in this regard, because there's no text that I know of (at least with respect to the later corpus) certainly informing that Ingwe, Finwe, Elwe necessarily awoke in any case. It may seem like fence sitting but I prefer not to know for sure in this case, and think Tolkien was 'right' (if indeed I am right about what he was doing here!) to give the Awakening of the Elves this added element.

Not that it does create a 'difficulty' for you or anyone. But anyway I don't feel I can say something so clear cut as Cuivienyarna and Q&E certainly tells the Reader that Ingwe, Finwe, Elwe did not awake because of sibling or marriage considerations.