2. Who filled Dumbledore's role in Timeline A, the one Ron went back to correct? If there was no one, it seems likely the school would have fallen apart.

My interpretation is there is no Timeline A, and the story is a self-contained time loop. Dumbledore existed because Ron went back and became him. It happens because it happened.

That doesn't seem to be how time works in the Rowling universe, though. Harry and Hermione have to avoid themselves when they use the Time Turner.

If there was no one, it seems likely the school would have fallen apart.

Maybe it did. Timeline A could have seen the destruction of Hogwarts, the death of Harry Potter, hell maybe not even his birth, basically, anything but the death of Ron. All he had to do was survive and go back in time to set things right...although that would put some kinks in the "Dumbeldore knows everything" point.

But then I'd thinking time travel and flowcharts and soon my head would hurt.

The thing is, in PoA, there is no previous timeline. It always happened exactly as they make it happen (As Harry says, "I knew I could do it because I'd already done it"). So there doesn't need to be a previous timeline, so long as Ron goes back and becomes Dumbledore.

As for the why that far, my guess would be to make sure that Dumbledore was in place/respected/whatever before Tom Riddle went to school, so that the relationship between the two of them would be in place ("Only wizard he ever feared" and all that).

That doesn't seem to be how time works in the Rowling universe, though. Harry and Hermione have to avoid themselves when they use the Time Turner.

But the time travel adventure there is a perfect example of what I mean: the Patronus saves Harry because Harry always went back in time to do it. There was no alteration in the timeline; the timeline existed in an "altered" state.

Um, right. Okay. I think we agree.

Actually, I'm hoping Ron goes bad. He's mad to make money, which leaves him open.

Hmmm. I'm willing to take the point about the previous timeline/inevitability, which may also answer my other questions -- he goes back to 18whatever because he's always gone back to 18whatever -- but it still seems pretty strange to me.

Nutty, thanks for your point about the growing realism as the characters age and the increasing disconnect as the adult characters remain tropes. As I get further into the series, this has been bugging me more and more, although I must admit that it did annoy me a bit from the beginning. I hadn't really figured out what it was that was bothersome, though. You put it perfectly, which is such a relief!

If Snape was a big nerd, wouldn't Hermione be the closest to him now

Snape wasn't the cool kind of nerd like Hermione. He wasn't quite smart enough, plus, although I don't remember from the books, it seems like he must have had bad hair. In fact, I don't see the child Snape so much as a nerd as a geek. But I only read each book once, not really being a Harry Potter fanatic (I save my fanatacism for Firefly) and it's probably six months since I read the most recent one, so I could be all wet on this one.

This is what is stopping me from stepping into the burgeoning HP fandom -- I just can't see doing all the reading it would take to know the canon. I read each of the books once, and I skimmed LARGE sections of the last one. I keep trying to reread and getting bored and wandering off.

Bring back Buffy when it and I were young.