I agree with this, dwtb, and Sam knows that I am moving to a more integrated understanding. But still, we see the limbic or amygdala hijack in posts on SR all the time. I don't know how it happened, I don't remember deciding to drink, I just did it / this voice tells me to go ahead and have just a couple / I don't understand why I drank again, I just got so angry or sad or .... And on and on.
While there may not be two separate brain states (or instead there may be many more, I dunno), it still seems to be a useful way of describing what happens in that an awareness that can lead to recognition and mindfulness supports rational decisions. We slow down, and the cognition moves from lymbic to cortex, and we get to act rationally. I think that 'playing the tape through' is another exercise that can accomplish the same thing.