Suesse

Interesting point, but they'd be really killing themselves in terms of testing required for something like this. It really does make more sense to just dump everything out at once... except for the fact that the 3.0 changes would break certain encounters.

Edit: I mean breaking encounters in a way that would make them much harder or near impossible. I doubt they care much about making fights easier. All the top guilds have already experienced hard-mode sunwell, T6, and T5, so nerfs are not really a problem. Warrior shield block changes, for example, would be pretty harsh for any crushing boss. It would also force either passive shear immunity or good luck on Illidan.