I'm wondering if it'll turn out that Ulfric was brainwashed during his interregation by Elenwen. I mean he goes back to Skyrim and decides to fight the Empire instead of trying to drive the Thalmor out. After all, the Empire had to renounce Hammerfell as an Imperial province when the Redguards refused to bow to the Thalmor. Why did Ulfric not do the same with Skyrim? Such a swerve would make a good basis for the final Skyrim DLC in my opinion.