Well.
That happened.
I'm rather hoping (too tired to put numbers on it, sorry) that Harry can summon a phoenix straight from the mirror-he never tested the claim that a phoenix only shows up once, after all...and now he's got the source of phoenixes right next to him. That's a gun that's just itching to fire.
"All your hallows combine" is fairly obvious, though the location of the stone is not entirely clear.
And then quirrel won a bet with dumbledore when it turned out that first-years could cast the patronus.
Fake-moody's statement that he'd get no more than a bloody nose...You woudln't want to try that in the MoR verse. one of the students might be tempted to test it. and if the've been in quirrel's wargames, well...
you get the idea.
cause in MoR, it IS largely practice-based. in cannon rowling left it vague.
...a last ditch effort to at least make their deaths quick, while opening up a window to hit the dementors with a point-blank patronus 2.0 without worrying about the guards? Not that I think it very likely, mind you. harry may be broadening his options somewhat, but he has a ways to go before he's quite THAT desperate.
It has occured to me that IF harry does obtain the sorcerer's stone...it's quite likely that quirrel will have been the one to get it out of the mirror, WITHOUT utilizing his leet magical skills.
Something of the real voldemort was leaking through-and the part that was leaking through was, essentially, his gibbering fear of death.
Which really, really won't help in trying to cast a True Patronus.