[Nerwen]

Morth, I think you've misinterpreted what jallanite is trying to say, which if I'm right (I may not be right) is that Tom's identity may be much like the mysterious briefcase in "Pulp Fiction". As you no doubt recall, there is neither an in-story nor an official explanation of the case's contents- it is an intentional enigma- but various characters in the film are definitely *supposed* to know what's in it.

That's just the first example I thought of, but I'm sure I can provide more if needed. In fact the fiction-within-a-fiction whereby a character is *held* to know "the answer" when in fact no such answer really exists is not all that uncommon.

In short, we can't possibly know who Bombadil is, but, for narrative purposes, Elrond can.