Considering how much of a threat technology can pose when combined with magic, one or more factions may have deliberately placed an ignorant pureblood into the position in order to keep knowledge of muggle developments marginal.
That implies he at least suspects Harry holds a horcrux...
If it existed and was semi-public knowledge, then Lucius would have made a priority of acquiring some for Draco.
Personally I'm assuming that Quirrelmort rescued Bellatrix to influence Harry. He now has first-hand evidence that Harry was engaged in a major crime, has shown Harry a part of the Wizarding world which he could never accept which was enabled by democracy, has shown Harry that Dumbledore isn't as proactive as Harry would want him to be, almost convinced Harry that a revolution is necessary, convinced Harry to lie to protect him, and has made Harry feel sorry for Bellatrix. Generating a 'false alarm' of Voldemort's return is a nice side effect as well if he doesn't plan on acting immediately, Dumbledore may well have just expended significant political capital too early. If he was planning on going through with the ritual, then he had Harry right there with him. (Although he could have just taken some blood while Harry was asleep, of course.)
The only motivation I can see for him to retrieve her otherwise is that he couldn't remember what happened at Godric's Hollow or to the Longbottoms, so he wanted to retrieve Bellatrix to find out, he regretted what he did to her (seems unlikely), or he's not Quirrelmort, and is really just a powerful but neutral wizard who wants to try and retrieve some of Slytherin's magics.
Ah, very well then. Thank you for clearing that up.
Well, I can mention a theory for the sake of discussion, but it's rather hypothetical.
When it occurred I was assuming that:
Dumbledore as a 'Great Wizard' embodied the virtues Eliezer seems to be emphasizing in the story, including intelligence, hard work, critical thought, and a certain amount of rationality.
Harry's Dark Side is one of Voldemort's Horcruxes or a portion of his soul.
Dumbledore is, at least partly, faking his senility to appear less dangerous to his enemies and make it more difficult for them to predict his action. He's still ready to make difficult decisions when necessary and is a competent leader during war, but feels a great deal of guilt which makes him extremely unwilling to ever escalate any conflicts, preferring passive approaches whenever he isn't forced to fight.
Amelia Bones killed Narcissa Malfoy, and Dumbledore claimed responsibility to protect her and give the Death Eaters the impression he was willing to respond in kind to the killing of non-combatants. He also implied threats towards Draco and/or the children of other Death Eaters, including Hogwarts students. This is also why he tolerates so much bullying at hogwarts, so that those same children will still be present in the event of the leverage being required.
Sirius Black was Mr Hat and Cloak. (Mostly wishful thinking I have to admit.)
Dumbledore really does has a good mental model of Voldemort.
The Canon Love Shield was changed somehow as it didn't fit with the MoR Emphasized Virtues (as I think of them).
Now, to quote.
http://www.fanfiction.net/s/5782108/62/Harry_Potter_and_the_Methods_of_Rationality
"Yes," said the old wizard, "it is time, Harry Potter." The back straightened, only slightly for the wizard had already been standing straight; but somehow even that small change made the wizard seem a foot taller, and stronger if not younger, formidable though not dangerous, his potency gathered about him like a cowl. In a clear voice, then, he spoke: "This day your war against Voldemort has begun.".... "It is important to understand," said Dumbledore, "that this book is not a realistic depiction of a wizarding war. John Tolkien never fought Voldemort. Your war will not be like the books you have read. Real life is not like stories. Do you understand, Harry?".... "No," said the old wizard's voice. "I do not think so. The Death Eaters learned, toward the end of the war, not to attack the Order's families. And if Voldemort is now acting without his former companions, he still knows that it is I who make the decisions for now, and he knows that I would give him nothing for any threat to your family. I have taught him that I do not give in to blackmail, and so he will not try." Harry turned back then, and saw a coldness on the old wizard's face to match the shift in his voice, Dumbledore's blue eyes grown hard as steel behind the glasses, it didn't match the person but it matched the formal black robes.
Although there isn't much/any direct evidence to base any theory on as far as I know, the suspicions my mind provided was that Godric's Hollow was the culmination of a lot of hard work and planning on Dumbledore's part, probably with the help of James and Lily Potter who may or may not have been capable of developing to the same level as Dumbledore. Since Snape is mentioned as being in the same category as Dumbledore and Quirrell, and I thought that Sirius was Mr. H&C who also seems to be on that level, and the Marauders are mentioned as being very capable, I'm assuming that Lily and James are on a similar level to their friends, or at least, were at roughly the level their friends were ten years ago, with some fluctuation at each skill since they probably had different talents.
The big weak-point that I noticed in my idea was that I don't know whether Dumbledore knew Voldemort had horcruxes or was using 'soul magic' at the time, so I'd consider further speculation a lot less likely to be valid.
One possible scenario is that Dumbledore knew Voldemort was developing Horcruxes, and was working with James and Lily to develop a way to use that against him, or detach his soul from his body while prevent him from reviving quickly in the same manner that the Diary Riddle did in CoS. When he heard about the prophecy from Snape he knew that Voldemort would try to kill the possible candidates and/or make a horcrux with their murders. (Although the latter seems less 'evil' and more 'arrogant symbolism', so unless the list was Quirrel(Mort)'s development after his first horrific failure, I'm not sure how likely it is.) He sent the Longbottoms and Potters into hiding while they developed the trap, then had the Potters switch secret keepers to Peter and used Harry as bait to draw Voldemort in. Whether Dumbledore expected the Horcrux to be lodged in Harry's head I'm not sure, but if he did, it may explain why he sent Harry to live with loving Muggles (and may have primed Minerva to be suspicious about how they treated Harry, and made harry defend on other occasions) in order to compensate for the handicaps of giving Harry a bit of Voldemort, while exploiting the edge of experience it seems to give Harry on some occasions to compensate for the huge experience gap between Voldemort and eleven-year-old Harry. In this scenario Sirius might have good reason to distrust Dumbledore, especially since Dumbledore had to keep quiet about who the real secret keeper was so his involvement in the trap wasn't revealed and he could potentially reuse it later unexpectedly, but would probably have been kept out of Azkaban by Dumbledore with some obligation to him. Dumbledore would have deliberately given Harry a love of Muggles to give him a deep conflict with Voldemort who is very much afraid of muggles, keeping Sirius away from his godson, probably causing some additional tension.
It would be very... consequentialistic of Dumbledore, which doesn't fit completely with his character as I see him, but at the same time by the end of the war 'everyone' had lost someone, people were being flayed alive, and he or his supporters were war criminals. If he thought there was a good chance of survival for Harry, especially, I could see it happening. A variation of this masterminded by Lily and/or James is also possible.
Another is that there was a trap, but it was purely defensive, and the way things turned out was unexpected. The Horcrux could have been part of Voldemort's plan to subvert the prophecy by fulfilling the prophecy, then turning the prophecy child into his pawns. However something interfered, presumably, since while it's possible Harry's politcal power is part of the plan to take over in a less violent manner, and that could be Quirrel's current plan, but the muggles have only gotten more powerful during his absence, and he doesn't appear to have taken his most loyal followers (or made some more in the same way he did Bellatrix) and imperiused some high ranking members of the armed forces and political establishment to start world war three during the inter-war period.
The third one was that either Lily or James managed to cast a killing curse on Voldemort, but it only separated his soul from his body, he wasn't outright killed. Possibly as part of someone's plan, possibly not, that part of his soul ended up in Harry, and the 'current' Voldemort doesn't have access to his memories, so he doesn't know what happened.
I wish it noted I wouldn't have mentioned this unless someone else raised the topic and wanted input...
A quick google couldn't find any link to the study itself, if you have a link, could you post it please?
Same as Silas.
The two don't have to be mutually exclusive, although finding the share of responsibility might be difficult.
I admit to only having watched scattered episodes and the pilot, but assuming that the alicorn transformation can only be granted to ponies one could argue upraising the entire population would have a negative effect on the other sapient species such as Gryphons. If she held that position she could even support transponyism inherently, but oppose immediate application until a parallel can be developed for other sapients.
Some possibilities: