I believe that Rand is simply a man who can channel that was taken over by Lews Therin. If you have ever read any of the Dragonlance series and read about Raistlin Majere, you will understand what I mean. If you recall, he never could channel until he found that he had NEED to. Also, once he did channel, I believe that because when he first cahnneled he was not in his own plane of existance, I believe that he ended up in the plane where Lews Therin's soul was resting, waiting for a body to be reborn into. Because of this, I believe that in the last battle, Lews Therin will take over Rand's body and in defending the world, his soul will be finally killed and be able to rest with Illyena, who will be killed also in this last battle, whoever that may be. Rand will be free of Lews Therin and will become the greatest male wielder of the one power in the world and become the first male Aes Sedai in over three thousand years.