POA Prongs Patronus

[Brenda]

No: HPFGUIDX 100410

Alina wrote:
> Harry kept on waiting for his dad to show up somehow,
> and then realized that it wasn't his dad he had seen, but his own
> time-travelling self. He produced the Patronus, knowing his could 
> this time because he had already seen himself do it several hours 
> earlier.


This is actually the part from PoA that REALLY REALLY confuses me, 
and this confusion was intensified after watching the film 
adaptation.  I'm wondering, are certain time periods destined to be 
revisited?  For example:

1. Hermione throwing the rocks to the hut so that they'll get out.
2. Hermione wondering if that's how her hair looks like from the back 
(that line cracked me up, i didn't think HErmione cared about her 
appearance too much just yet..) and the "past/before" Hermione 
hearing herself.
3. Of course, there's the werewolf-calling-out, and the Patronous, 
etc etc..

My question is, will those incidents have occurred if they didn't go 
back in time?  It certainly seemed to me that they happened because 
the future H/Hr had interferred, and somehow the circumstances at 
that time *knew* that they were to be revisited and corrected??  This 
strongly reminds me of a scene from The Matrix with the Oracle and 
Neo. (this, of course, is a very rough transition of the 
conversation, I'm at a school library right now, I don't think the 
staffs will be too pleased if I started watching the MAtrix here...)

- Oracle: "Oh, and don't worry the vase"
- Neo: "What vase?" [and at that instance he breaks it..]
- Neo: "how'd you know.."
- Oracle: "the real question is, would you have broken it if I didn't 
tell you?"

Also, whatever happens to people/lives/circumstances that are not 
involved with those who turned the Time Turner?  Do they just simply 
go back in time and re-live the whole thing without knowing?

Brenda (who is now more confused than ever, and who also started 
embracing her always-confused-and-dull brain ever since joining the 
group.. wells there HAVE to be the silly/non-perceptive ones for 
someone else to be smart.. it's all relative after all..)