So you had had a Word of Brandon that had said that Tien was on his way to becoming a Lightweaver. My question is, did he ever actually become a Lightweaver; did he speak an Oath, and if so, did he bond with a Cryptic?
That's an excellent question. If you look closely through the first book, you will see Tien having some slight Lightweaving effects. In the back of my head, he was where Kaladin was during most of the first book, where it wasn't really official but there was a spren hanging around. He was very close to-- by the time he left, already done that. I would say he never actually managed to get that bond working... Otherwise, perhaps, things would have played out differently than they did.