Well, I've never been convinced by the story that three ships were enough to save all the Faithful Numenoreans - unless of course at least one of them was an odd looking ship that was bigger on the inside than the outside.....
More seriously, Tolkien's fascination with time travel is well known & the idea of a crossover Doctor Who/Lost Road/Notion Club story doesn't seem too out of place....
Cybermen rounding up the Faithful in Numenor..... Daleks at the fall of Gondolin... Hobbits in gasmasks wandering around asking 'Are you my mummy?
