I was reading reviews and commentary on random ljs, and came across a very interesting entry by garlandgraves, with a very excellent point:
But back up a moment: Snape gazes at the Headmaster for a moment. Two accomplished Legilimens do nothing but look at each other for a moment in the midst of a heated battle situation, and we are to assume there is nothing passing between them?
God, I feel stupid. Of course, of course, of course. In fact, this really doesn't clarify all that much, because antyhing could have been communicated in those circumstances. But this would clear up everything that went on between them, really, no matter what you interpret their words to say - because they're not just relying on what they know of each other. They're also leaning on their minds.
I wonder if Snape gave into the plea, whatever it was, or not. I'm starting to convince myself that some of the revulsion is revulsion at Dumbledore's state - the fact that he's reduced to begging, however reserved the begging is, the fact that the tables have been turned, that Dumbledore is in his hands now, and he doesn't know what to make of it. He's too used to being in debt.
Now, I wonder if he actually wants power? In some ways, yes, and in others, I can't really imagine it... he wanted a name for himself, he wanted respct; that's obvious. He enjoys patronizing and frightening his students, and knocking Harry around whenever possible. Power over other people's emotions, in a manipulative way; he likes that. But this power over other people's lives... I wonder... whether that wouldn't be the worst part of being a Death Eater for him now, to crush other people beneath him, when this time they didn't have an escape. The sort of thrill he wouldn't want.