I tend to think any line of action which ends up with Riddle losing his body and having to fall back on his horcruxes, given that he apparently wants his old powers back based on his efforts to get at the ingredients to revive himself and/or the Philosopher's Stone, probably contained some element of accident.
Also, the act of training his prophesied enemy, one of whom is bound to vanquish "all but a remnant" of the other, doesn't sound like a great way to serve his own interests. It's not like he's likely to subvert the prophesy and gain a powerful ally, it's just another avenue to empowering the person who's his greatest threat.
If I were in Quirrell's place, and knew about the prophesy, I would be wondering "in what way can I ensure that whatever person this prophesy refers to will be least likely to be able to defeat me, assuming our conflict is inevitable?" Keeping in mind that if I try too hard to make a candidate into a nonviable threat, the prophesy will probably turn out to be referring to someone else.
Edit: New thread posted here.
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 86. The previous thread has long passed 500 comments.
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: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16.
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: