I Found the Entwives!

[Formendacil]

Very succint and easy to read, Alcuin. I fear, however, that you're missing the entire direction that the Phantom is going here. He said, and I paraphrase, that he has found a crackpot theory that he thinks he can logically make a good case out of, and he intends to ride it out for all it's worth, for the pure fun of it.

See, you're arguing as if any theory about the Entwives was reasonable. I don't think anyone (other than Ardamir the Blessed and his ilk) actually thinks we can find the Entwives. We're just looking for a coherent theory that COULD logically not contradict the books.

That said, you could be on the right track with the Elven magic, though I find the Phantom's counter-argument about boastful Haldir to be more convincing. Perhaps it was a secret that Haldir wasn't allowed/didn't want to reveal? Kind of like having Dwarves walk blindfolded through the Naith.