Without endorsing any part of this comment dealing with events which have yet to take place, I congratulate user 75th who receives many Bayes points for this:

http://lesswrong.com/lw/bfo/harry_potter_and_the_methods_of_rationality/6aih

Hermione is dead. Hermione Granger is doomed to die horribly. Hermione Granger will very soon die, and die horribly, dramatically, grotesquely, and utterly.

Fare thee well, Hermione Jean Granger. You escaped death once, at a cost of twice and a half your hero's capital. There is nothing remaining. There is no escape. You were saved once, by the will of your hero and the will of your enemy. You were offered a final escape, but like the heroine you are, you refused. Now only death awaits you. No savior hath the savior, least of all you. You will die horribly, and Harry Potter will watch, and Harry Potter will crack open and fall apart and explode, but even he in all his desperation and fury will not be able to save you. You are the cord binding Harry Potter to the Light, and you will be cut, and your blood, spilled by the hand of your enemy, will usher in Hell on Earth, rendered by the hand of your hero.

Goodbye, Hermione. May the peace and goodness you represent last not one second longer than you do.

When I first saw this comment, it was downvoted to... I forget, -6 or something. Going by the percentage score, at least 11 people downvoted it. From the replies, some people didn't like the tone of apparent certainty with which 75th spoke. Sounded uppity to them, I guess. It was at +3 before I linked to it on /r/HPMOR.

I wanted to say something at the time about that, and how penalizing people for sounding certain or uppity or above-the-status-you-assign-them can potentially lead you to ignore people who are actually competent, but at the time all I could say was "Why are people downvoting this? It's a testable prediction" whereupon it climbed up to above 0.

Everyone who downvoted 75th or agreed with the downvotes at the time, please take note. Speaking in a tone of what seems-to-you like inappropriate certainty does not always indicate that someone is arrogant. Sometimes they have seen something you have not.