[William Cloud Hicklin]

Well, yes, IF one assumes that Tolkien was interested in synthesizing two (or three) alternate theories, rather than just picking one and chucking the rest.

I find it interesting that well after both the Myths Transformed essays and the publication of the LR, he was still writing pieces in which Pengolodh was relating lore to Aelfwine- the old Lost Tales-era transmission theory which can't be shoehorned into either of the others without a hydraulic jack!

So at various times he had 4 (or 3-1/2) theories, as follows:

1) 5th century Angle Eriol discovers the Lonely Isle (the future Great Britain) and learns the Elves' history, and witnesses its end. Recorded in "Golden Book of Tavrobel," presumably somehow preserved at Warwick. Essentially "true."

1a) 10th century Anglo-Saxon Aelfwine discovers the Lonely Isle (not Britain) and learns the Elves' history from (Rumil and) Pengolodh. Recorded in Old English, which Tolkien the OE scholar "discovered" and "translated." Essentially "true."

2) Bilbo Baggins translates history from writings in Quenya/Sindarin kept at Rivendell, records them in the mutivolume Red Book, copied in the "Thain's Book" in Gondor, ultimately "discovered" and "translated" by Tolkien the"Westron scholar" along with the earlier parts of the Red Book. Source materials in Elrond's library, and recollections of the Wise, essentially "true."

3) Numenoreans/Dunedain write down "history" which at least in its earlier parts is mingled with Mannish myths and garbles the actual facts as known to the Eldar. Transmission uncertain, but presumably similar to (2). Considerable parts not "true."

There are some real difficulties trying to reconcile any of these, like "solving" a jigsaw puzzle by hammering together pieces that don't actually fit with each other.