That darn Prophecy again.. Re: Thin air/Choices

[justcarol67]

No: HPFGUIDX 140329

Carol earlier:
> > Voldemort kills Lily, activating the ancient love magic. Voldemort
 AKs Harry. The AK bursts from Harry's head, leaving a jagged scar 
> <oversnip>
> 
Sandy aka msbeadsley responded:
> Am I missing something, or is there a problem with this in that the
incidental Priori Incantatem in the graveyard didn't show Voldemort's
wand having done anything past Lily's death? Are you inferring that it
didn't show because it didn't succeed? I have to say regretfully that
I have never liked this notion; within this scenario, the wand did
cast the spell, regardless of the result or lack of one. Something
should have appeared. Shouldn't it?
> 
> 
Carol replies:
Yes, I think the Priori Incantantem failed to show the AK that
rebounded from Harry onto Voldemort because it was a failed
curse--there was no shadow self of Harry to show. Even Harry's scar
was caused by the repelled AK *bursting outward* and not by the
original spell cast by LV and besides the Priori Incantatem would have
no way of showing such a nonstandard result. (I don't think the PI
shows every spell, BTW, only AKs, Crucios, the silver hand, and
possibly other spells that can be physically represented. I don't see
how it could show an Imperius or a memory charm, for example.)

JKR has made it clear in all the books and in her interviews that the
killing curse aimed at Harry rebounded onto LV. Clearly this failed AK
is a different curse from the normal and successful AK that killed
Lily. When Voldemort says (ungrammatically) in GoF: "My curse was
deflected by the woman's foolish sacrifice, and it rebounded upon
myself," I read the words to mean that Lily was already dead and that
the curse rebounded from Harry because of the ancient magic involved
in her sacrifice. But if she simply stepped in front of him and took
the AK aimed at him, something else would be necessary to explain how
*Harry* survived an AK. Unless Harry himself was struck with a killing
curse, as all the books and interviews imply, there's nothing
miraculous about his survival and no need to bring in the concept of
ancient magic. So IMO, three AKs were cast that night, but the wand
showed only the successful ones (James and Lily, along with later
victims), not the one the AK that rebounded. 
 
On a related note, people keep looking for a reason why Voldemort
would be willing to spare Lily. I don't think he cared about her one
way or the other. She was just a "silly girl" standing in his way. It
seems to me quite obvious that killing her was the only way to get her
out of his way so he could reach his real target, Harry. He was not
trying to create a Horcrux. He was trying to prevent the prophecy from
being fulfilled by destroying "the one with the power." Maybe he
intended to celebrate afterwards by creating his final Horcrux from
this highly significant murder, but the business at hand was killing
the infant who had (or would in future have) the power to destroy him.

Carol, who also wanted to say something about Diary!Tom being a memory
rather than a soul fragment (the diary started out as something other
than a Horcrux) but finds that mixing topics tangles up the threads