@wheatbeer:
It’s hard to know how consistent the magic is or isn’t when there’s very little transparency about the nature of magic itself (at least in the Hobbit and LOTR).
I wish Tolkien had gotten around to that particular appendix … how else are we supposed to know how many times Gandalf can cast Magic Missile before he has to rest?
The thing about Tolkien’s “magic” is that it is much more spiritual and intrinsic than generic, alchemic magic found in D&D, Harry Potter or other fantasy works I have seen. By that I mean this is not an RPG. Tolkien rarely describes the abilities of creatures/beings in his works as being magical. If he does, it is usually referring to something evil or somehow twisted in purpose. But all you D&D/fantasy people will have to correct me if that is essentially the same definition for “magic” used elsewhere, though that is not my impression.
In his prominent essay “On Fairy Stories” Tolkien said of magic:
“Faerie itself may perhaps most nearly be translated by Magic - but it is magic of a particular mood and power, at the furthest pole from the vulgar devices of the laborious, scientific, magician.”
Tolkien’s Wizards, for example, are described as “claiming to possess, and exhibiting, eminent knowledge of the history and nature of the world… the Order of Wizards was quite distinct from the wizards and magicians of later legend.” (from the essay on The Istari from Unfinished Tales) There is much more to be gleaned of Tolkien’s “magic” in The Silmarillion and Unfinished Tales than in The Lord of the Rings or The Hobbit, so you are pretty accurate there.
By saying it is much more spiritual, I mean that Tolkien bases his take on magic to something philosophical (from his perspective, spiritual); a contradiction of invisible essence or power, one of which is wonder, enchantment, creativity and art, and the perverted form which is the creation of the artificial, use for control and conquest. If you have not read The Philosophy of Tolkien, by Peter Kreeft, (http://www.amazon.com/The-Philosophy-Tolkien-Worldview-Behind/dp/1586170252/ref=sr_1_1?ie=UTF8&qid=1357264825&sr=8-1&keywords=philosophy+of+tolkien) I cannot recommend it highly enough. It will explain much of the mind of Tolkien and the meaning of his work.
With the explanation above, it is both impossible and improper to reduce Tolkien’s “magic” to hit points and recharge rates. His fantasy is the foundation for all that exists today, but much of what is around today cannot translate into Tolkien’s world because has been … diluted and empiricized. They do not relate to the same conception of magic.