[Aiwendil]

I can half agree with you, but all those writings remained unfinished, or they became theological tracts (Athrabeth), or they simply repeated or were re writings of already existing things.

But the tendency toward revision and leaving things unfinished is true of all the Silmarillion material, pre-LotR as well as post-LotR. And "Wanderings" and "Aldarion and Erendis" were wholly new, while the Narn and the revisions introduced a lot of new material. You're right, of course, that this isn't the place to discuss this in any depth, but it does have some bearing on your point about the loss of magic.

Mithalwen wrote:

or the sub- "There was a lover and his lass" poetry....

You do actually bring up an interesting point, and one that has some bearing on the Art vs. Nature conondrum. That is, though Tom is always speaking in verse and lapses into outright song very frequently, none of his poetry is particularly good. And I say this as someone who likes Tom Bombadil. When he rhymes, the rhymes are often forced (whatever would he do if he didn't have yellow boots?) and the meter is often uneven. Even the Hobbits are better poets than he - let alone "Earendil was a Mariner", Frodo's lament for Gandalf, or Sam's song in Cirith Ungol; I'd even take the Bath Song over Tom's stuff for sheer poetic value. So in the sense that he's constantly singing, Tom does seem tied to Art; but his Art is completely uncontrived - he doesn't even take the time to contrive it that the songs he sings are good songs; he simply sings without thought of artistic value. So perhaps he is one with Arda, and his songs do not represent any actual artistry or sub-creation on his part; they are simply part of him because he is part of Arda, and because Arda is the embodiment of the Ainulindale. He is not an Artist; he is Art. And Art does not have Artistry.