So, I was just wondering something about the Letters in the Way of Kings book. How does Hoid send the letter to the dragon?
I very much doubt that there is a Cosmere-wide postal service at any worldhopper's convenience. Even if there was, something like that would probably be to blatant for Hoid.
I'm not even sure if the Letter is an actual letter, maybe Hoid uses some sort of magical device that sends out messages. Just a random thought that occured to me while re-reading Way of Kings.