Harry could destroy his own reputation in order to save Hermione, by (for example) threatening to forever abandon Wizarding Britain.
Shouldn't they take that for granted already? I mean obviously he's going to have absolutely no remaining loyalty to the state - or at least the power structure - that did that to him. They should all expect to die whenever Harry finds it convenient to overthrow them. Or is that just what I would do?
(Any sane politician who was planning to make that sort of move against a potential emergent power like Harry would also see to it that they were killed, crippled or framed as a matter of course. You don't go around recklessly making enemies and leaving them free to gather power.)
Apart from Dumbledore and Lucius, none of them are likely to take an 11-yo child and his promises of enmity and revenge at all seriously. "Enough talk, he'll be late for his classes." And even if he might become a political counter of some significance in a decade, or a few decades, they wouldn't expect him to hold a grudge that long - normal children don't often do that.
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: