I think he just didn't want to believe that.
"Are you all lost?" cried Albus Dumbledore. "She is too young! Her mind would not withstand it! Not in three centuries has such a thing been done in Britain!"
The leading article, written by some name that Harry didn't recognize, had called for the minimum age for Azkaban to be lowered, just so that the twisted mudblood who had defaced the honor of Scotland with her savage, unprovoked attack upon the last heir of a Most Ancient House within the sacred refuge of Hogwarts could be sent to the Dementors that were the only punishment commensurate with the severity of her unspeakable crime.
This is a definite break from the historical record.
EDIT: New discussion thread here.
This is a new thread to discuss Eliezer Yudkowsky's Harry Potter and the Methods of Rationality and anything related to it. With two chapters recently the previous thread has very quickly reached 500 comments. The latest chapter as of 17th March 2012 is Ch. 79.
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.
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: