One interesting clue I noticed last night while re-reading HPMOR to my wife as a bed time story is that Snape is essentially ordered by Dumbledore to stop reading students' minds as a condition of his blackmail-agreement with Harry (Chapter 18), but we see later that Snape is clearly still reading minds without permission when he reads Alissa Cornfoot's mind while she is fantasizing about him (Chapter 28). Previously I hadn't thought that there was any real reason for that interlude in Chapter 28, but now I see that it tells us information about how Snape doesn't follow Dumbledore's orders.
I'm unsure that is an accurate description of the text.
You are more or less right about chapter 18. First, Harry makes his demand regarding Snape:
"Ah... he's also to stop reading students' minds."
Then there is this corresponding line within the compromise Dumbledore offers:
He will promise to only read minds when the safety of a student requires it.
We don't observe this promise actually being made. And we aren't even assured of when it would be made. A pointlessly legalistic take on the terms could be that Snape will make that promise a...
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: