Quirrell could have decided that their overall grades should reflect only their ability to defend themselves, and so chosen to adjust the non-exam grades such that each student's overall grade (with the final included) matches his assessment of that student's defensive ability.
(This is really a more detailed version of your second guess.)
It could mean that, by surviving this long, Harry has exceeded Quirrell's expectations.
New chapter, and the end is now in sight!
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 103.
There is 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.)
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: