[Update: and now there's a fifth discussion thread, which you should probably use in preference to this one. Later update: and a sixth -- in the discussion section, which is where these threads are living for now on. Also: tag for HP threads in the main section, and tag for HP threads in the discussion section.]
The third discussion thread is above 500 comments now, just like the others, so it's time for a new one. Predecessors: one, two, three. For anyone who's been on Mars and doesn't know what this is about: it's Eliezer's remarkable Harry Potter fanfic.
Spoiler warning and helpful suggestion (copied from those in the earlier threads):
Spoiler Warning: this thread contains unrot13'd spoilers for Harry Potter and the Methods of Rationality up to the current chapter and for the original Harry Potter series. Please continue to use rot13 for spoilers to other works of fiction, or if you have insider knowledge of future chapters of Harry Potter and the Methods of Rationality.
A suggestion: mention at the top of your comment which chapter you're commenting on, or what chapter you're up to, so that people can understand the context of your comment even after more chapters have been posted. This can also help people avoid reading spoilers for a new chapter before they realize that there is a new chapter.
That's an interesting point. In context of that, consider the following -- Harry is now [end of chapter 54] without protection from the Dementors, thus gone entirely to the 'dark side,' which in Harry as in most is rather Slytherin. That means that Harry is now in the perfect position to see how he's been manipulated, and act against on it: specifically, betraying Quirell and going with his first story "He made me do it." He can even attribute his attacking an Auror who thought about Moody* to the Dementors and potentially get away with the whole thing.
Just something to consider.
* I misread, but the point remains.
Not Moody, but a cameo Auror who thought about Moody