I think that best describes my own attitude as well.I have not had such a feeling ever - but then it is not something I desire particularly, other than out of curiosity.
1: There is nothing separate and there never was. That is just an illusion that comes into play due to our inability to express what is.
2: It feels liberating (as in "things are okay the way they are") on the one hand -- on the other it is weird as previous thinking patterns are recognized as making not much sense any more. This is maybe the cognitive dissonance you suggested.
3: What comes to mind here is where you requested me to type something and then to describe "who" did it. There I had this clear realization that "nothing is doing it". Whether that was substantially different from any realization that occured before, I cannot really say.

