In many ways I agree with all of you. I am still totally convinced that Tyrol would leave but I do have my own reasons why he would.

1. Have you seen the way he has been treated since he was revealed to be a Cylon. They will never be accepted, he has to fight tooth and nail to get anything done and it is always under this cloud of suspicion that is not warranted as Tyrol is one of the most loyal, devoted and caring ‘people’ Adama has had on that ship and finding out he was a Cylon did nothing to change that attitude.
2. He does not see a future with the humans on Galactica. Again, they will never be accepted. The Cylons now feel as though they are able to procreate on their own and they see their own future as one alone, away from the humans and away from Cavil.
3 There is nothing tying him to the Galactica. That died with Nicki being Hotdogs father. He has saved the ship, once again, and being made Chief by Adama was a thing of convenience for Adama and not a true acceptance or recognition of who Tyrol is and what he means to the ship, he was just the guy best suited to fix Galactica. It would have meant more to Tyrol if Adama had apologized and asked him to help him fix Galactica, doing the whole Chief ceremony didn’t win Tyrol over.

I don’t agree with the idea of payback. Tyrol does not feel as though he needs to get anyone back. He just wants to live and let live. His mind set will become clearer over the course of the show but this is genuinely where he is.
Tyrol would not see it as bailing. The ship is fine, Adama is fine, he does not see his leaving as bailing on the Galactica or leaving it in the lurch. He is Chief in title only, he is not a human, is not truly a part of the military anymore. Tigh will stay because his loyalty is to Bill Adama, in that aspect Ellen is correct. Tigh is still not fully accepting of the fact that he is a Cylon.
Tyrols judgement is clouded and we can see that by the fact that he ignores the pleas of Anders to stay with the ship.
All will be revealed, have patience my young apprentices….

Jane Espenson is one of the finest writers I have ever met. She was not just a writer of singular episodes but she is a true force in the breaking of stories, the shaping of each script, the development of characters and is always makes herself available for questions and discussions. Let’s not forget that it was Jane who wrote the incredible episode where Adama busts the Chief down to private, one of my favorite scenes of the entire show.

Last nights episode was more of the ‘information’ ep like the last one. The remaining few eps will really inform this episode.

Have patience….

AD