His attitude after hearing the prophecy can be summed up by his words to McGonagall, which are consistent with everything he does thereafter
I would say that his request to McGonagall is consistent with my theory - he knew that her attempts to stop Harry would have the opposite effect. I am guessing that Quirrell has some alternate interpretation to the prophecy.
One possibility for this is "The End of the World" corresponds to an change to the natural order that makes the world unrecognizable, such as the removal of mortality.
It is possible that instead of burning up his own life to destroy all the dementors or defeat death, Harry could burn up some stars, which could explain the rest of the prophecy.
I'm not saying that I am correct, but I still see no actions that are inconsistent with my theory.
I think part of the confusion is that we are interpreting the punctuation differently. I don't interpret your second quotation (first quotation from the text) as meaning that he was happy, until interrupted by hearing the prophecy, but rather that the prophecy was the reason he had smiled.
Regarding the sequence of events, here's how it goes:
...Trelawney, who had been sitting behind him on the two-person broomstick that had just blazed through Hogwarts burning directly through all the walls and floors in their way, hastily pulled herself off and then sat down hard on the floor, a pace away from the red-glowing edges of a newly made gap in the wall. The woman was still breathing in gasps, bending over herself as though she were on the verge of vomiting out something larger than she was.
[Quirrell analyses the emotions he'd felt coming off Harry
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 99, 100, and 101. The previous thread is at nearly 500 comments.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system.
Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: