but Harry, Ron, and Hermione are improbably able to defeat it without doing much in particular.

I haven't read much Hary Potter fanfiction, but what I have, including HPMoR, tends to up the difficulty considerably, and makes this apparent by having the characters use the same trick that Ron knocked out the canon troll with to little or no effect. (In this case, Eliezer made it clear in Quirrel's first class that that trick would be dreadfully unlikely to work.) Is this a trend in HP fanfiction (in which case, it seems to fall into the class of "taking HP fanfiction tropes and doing them better" that Eliezer's been following)? Or is my sample size too small?