Now I understand that I was expecting D&D to do things D&D doesn't do, can't do, doesn't want to do, and that the fact the game kept insisting it could do these things makes me a little bitter. Because I believed it.
So I've moved on to FATE, and my group is loving it, because FATE is a system that supports the game experience we want to have. D&D isn't inherently bad (although it has some abysmally stupid elements kicking around), but it isn't what it told me it could be, and it's not what I want.