[Beanamir of Gondor]

Tolkien is [was] very talented- but so are many of today's science fiction and fantasy authors.
Take Margaret Weis and Tracy Hickman, for example. They wrote the Darksword Trilogy, which was easier to read than LOTR, but Thimhallan was still obviously a very complicated world to create. It's very hard to try and explain the concept of the Living being those who possess magic, and the Dead being those who do not.
Perhaps Tolkien did enter a secret portal somewhere. But I just think he was a genius, that's all. [Not to try and disprove any of your theories. I'm just a stick-in-the-mud.]