Dumbledore didn't say that he caused the fights between Lily and Snape. He said this:
Lily thought one of her friends was writing them and they had the most amazing fights.
"And", not "therefore" or "so". Bear in mind that this is the same scene earlier in which this takes place:
"And of course, most people who come to my office want to see Fawkes."
Dumbledore was standing next to the bird on the golden platform.
Harry came over, rather puzzled. "This is Fawkes?"
"Fawkes is a phoenix," said Dumbledore. "Very rare, very powerful magical creatures."
We're told in big bright flashing letters not to take Dumbledore's implications in this scene at face value. And we already know why Lily and Snape actually fought: because Snape was turning evil! His best friends were wannabe Death Eaters! That's why Lily actually cut off their friendship, not because of jokes written in a Potions book.
If anything, it seems like Dumbledore was trying to get Lily to think of Snape as someone who could be lighthearted and joke around, as someone who could put a smile on her face, to try to get her to have feelings for him so she could pull him away from the Death Eaters! Some parts of MoR!Dumbledore may be a mystery to us, but his desire for people to choose the light over the dark is patently obvious. Dumbledore would never, ever ruin someone's only chance to save themselves from serving Voldemort. He wouldn't.
it seems like Dumbledore was trying to get Lily to have feelings for [Snape] so she could pull him away from the Death Eaters
I doubt it. Eliezer originally thought that Lily was dating Snape, the passage was changed to refer to her "one of her friends" after readers pointed out that they'd never dated. And if they were originally assumed to be dating then Lily would have already had feelings for him - no need to meddle like 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: