In the EotW, Rand has a dream while he is in the room where Tam is resting after being healed by Moraine.

"From the center of the furious vapors a mountain thrust upward, a mountain taller than any he had ever seen in the Mountains of Mist, a mountain as black as the loss of all hope. That bleak stone spire , a dagger stabbing at the heavens, was the source of his desolation. He had never seen it before, but he knew it. The memory of it flashed away like quicksilver when he tried to touch it, but the memory was there. He knew it was there."

Is this a foreshadowing of Rand's dramatic realization that occurs on Dragonmount at the end of tGS? Were the seeds of knowledge buried deep within him from the very beginning that he and LTT were one?

Perhaps we will have to wait until the end of the entire series to fully comprehend how RJ laid the threads of foreshadowing.