
Someone who has read the novelization of Revenge of the Sith explained to me that Yoda's sudden retreat from Palpatine and his self-exile are more fully fleshed out in the book. Yoda realizes that the ascetic training to which he has subjected the Jedi for some 800 years is wrong-headed and it is his own errors that have led to this downfall. He retreats in the face of disaster to try and rethink the ways of the Jedi so that when opportunity arises for their return he will be ready to teach in a better, more flexible style that will lead to a more resilient race of Jedi.
Or something.
Anyway, driving to work today I was thinking about this idea and suddenly imagined Yoda's interior dialogue upon this revelation:
Up I have fucked! The pooch have I screwed! A bozo I have been, teaching this way! Such an idiot, who knew that I was?
Of course, he then apparently went off to the swamp and gave it very little further thought, since his training methods as regards Luke don't much reflect this kind of change. (My personal theory is that Yoda had decided that the Jedi and the Sith needed to go, and he intended that Luke kill Palpatine and Vader by sacrificing himself, thereby ending the line of trained Force-wielders in the galaxy. But that's the nihilist in me.)