I decided to collect the stuff about these recent updates that confuse me, and when added together two were in the shape of a theory!

"Dumbledore was quite correct," Professor Quirrell said, shaking his head as though in wonderment. "He was also an utter fool to leave the Hogwarts Map in the possession of those two idiots. I had an unpleasant shock after I recovered the Map; it showed my name and yours correctly! The Weasley idiots had thought it a mere malfunction, especially after you received your Cloak and your Time-Turner. If Dumbledore had kept the Map himself - if the Weasleys had ever spoken of it to Dumbledore - but they did not, thankfully."

Even Quirrell is confused! Wow!

So... Dumbledore did know all along, just like cannon, and sent the map to the twins for plausible deniability. He can get away with that because he doesn't mind when people think him a fool. And he really needs Querrellmort to think of him as ignorant so he will play the role perfectly... well Voldemort said he could play chess.

In the last thread roystgnr wrote

Harry figures out Quirrell's identity almost immediately after Snape casts some sort of "Dispel Magical Confusion", yet the only character who would have the knowledge and incentive to magically confuse Harry about this is Quirrell himself, who seems to be incapable of directly using magic on Harry or Harry's magic.

That is totally something I wouldn't have figured out on my own. Well, the first part. I had just put that up to Harry not wanting to see ill of his friend, but magical obfuscation makes sense too. Oh, but someone else had the knowledge if the first theory is right. Someone who used Legilimancy on Harry in chapter 19 and that's just when Harry found out about it!