First, Shards of Orr isn't technically close, the two dungeons are across the Sea of Sorrows from each other. Shards of Orr just seems close because we travel through an Asura gate to get to Gadd's Encampment.
Second, if the Aggression Bloodstone is linked the Necromancy (and I assume your throughts for the others are: denial=Mesmer, preservation=monk, and destruction=elementalist), then a better support for that would be the non-hostile and hostile undead on the second floor, near the 3 Plinths and 2 broken Monoliths, just before the exit to level three.
Third, I hope in GW2, ANet professions to have magic only related to the bloodstones (Ritualists, Assassins, and Dervishes, which Bloodstone do their's come from?)
Edit: Wow. Maybe I should read through the thread. I looked at the OP and saw the whole Bloodstone=Profession thing >.<
I'l read through tomorrow or something. I should read through a ton of the other long threads as well, at least the OP of them. Would give me something to do when I'm bored. And maybe I can think of something to add or another new theory for some discussion on here.