(The HPMOR discussion thread after this one is here.)
This is a new thread to discuss Eliezer Yudkowsky's Harry Potter and the Methods of Rationality and anything related to it. There haven't been any chapters recently, but it looks like there are a bunch in the pipeline and the old thread is nearing 700 comments. The latest chapter as of 7th March 2012 is Ch. 77.
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.
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.
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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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.
The movie 'Groundhog Day' is about a man who relives the same day over and over again repeatedly. Because the day is reset, he is able to re-play each interaction with any person repeatedly until he can convince them of whatever he wants or work around them. Eg, he finds the hottest woman in town. The first day, he hits on her and is shot down but learns of her highschool. The second day, he says 'hey, didn't we go to highschool together at...?' He is quickly shot down again, but gets more information to keep the conversation longer. This repeats until he eventually gets her to have sex with him.
In chapter 77, H&C performs a similar hack. He tries to convince her, then obliviates her memory and uses his gained information to convince her even more, etc. Instead of resetting the day, he is resetting her mind back again and again. After enough iterations, he'll know exactly the right things to say to convince her to do whatever it is he wishes. As hinted in Chapter 77, what we viewed was not the first nor the last iteration of the attack.
If he is not constrained by ethics, he can also conveniently erase earlier memories of Hermione, if he suspects it would help to persuade her to do what he wants.
Effect - Dark!Hermione or at least different than she was before.