[PTeppic]

Although I think #1 is normal story-telling, revealing a key point a bit at a time, from different perspectives, the rest does make for an interesting theory.

We know thee must be more to Dumbeldore - "I don't need an cloak to make myself invisible" and his almost precognitive sense about what Harry will be doing and able to do each year suggests a very powerful powerful wizard. So some of the things he's done, like the above, appear to defy logic.