The new thread, discussion 13, is here.
This is a new thread to discuss Eliezer Yudkowsky's Harry Potter and the Methods of Rationality and anything related to it. With three chapters recently the previous thread has very quickly reached 1000 comments. The latest chapter as of 25th March 2012 is Ch 80.
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: one, two, three, four, five, six, seven, eight, nine, ten, eleven.
As a reminder, it's often useful to start your comment by indicating which chapter you are commenting on.
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:
You do not need to rot13 anything about HP:MoR or the original Harry Potter series unless you are posting insider information from Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).
If there is evidence for X in MOR and/or canon then it's fine to post about X without rot13, even if you also have heard privately from Eliezer that X is true. But you should not post that "Eliezer said X is true" unless you use rot13.
As we know, Harry's idea of double memory-charm has not been presented to the Wizengamot, which is a good thing; not only is it low status, as Harry realized, it's also unlikely to work, as Snape pointed out. Also, that's not what happened.
Hermione has been told the right lie, to lead her through the right emotions - a growing suspicion towards Draco, mainly - and then she was Obliviated, and told the same lie over again, went through the same emotions again, and again. If the sense of disorientation isn't a problem, she could have been looped through just the final, triggering sentence. Comulative effects had left her with the reoccuring thoughts and nagging doubts, the obsession we were told about. Even the idea of confronting Draco at the next battle, or keeping her doubts to herself could have been planted this way.
Hopefully it will be seen as a typical Voldemort-like cleverness by enough of the Wizengamot for the rest to work. In fact, redirecting Lucius's anger towards the real perpetrator should be doable, and most of his faction (politics!) would be eager to accept Harry's suggestion that Dumbledore was foolish enough to let an agent of the Dark Lord teach at Hogwarts - I doubt it would be a good idea to reveal the truth too early.
Quirrell, who, I think, is still held within the Ministry, will be brought for questioning, and revealed to be Voldemort. Whether it will be his power or the Bystander Effect (the title of the next trigger warning page) that holds the Wizengamot back long enough, I don't know. Actually, a single threat could make most of them hesitate long enough... Than, just as planned, he tries to kill Harry, explodes, then it's cheers and Butterbeers all 'round.
Harry will choose to cooperate with this plan because he will see it's aim wasn't to kill his friends - Draco could have been left for dead, and wasn't - and because he doesn't have five days to think of anything else.
It would be a serious change in the story and, with Quirrell gone, he couldn't fulfill his promise of both Slytherin and Ravenclaw winning the House Cup - but these things would not motivate Voldemort to pass on this opportunity, I think.
Your explanation of the Groundhog Day attack is the only one I've seen so far that makes sense.