I do this often, apparently. My BF tells me, "You know, I had another conversation with Jo-Jo last night" and I can usually remember only bits and pieces.
This happens after I have taken my sleeping meds and I am just about to fall asleep. We think it has to do with my defenses are down as I have major control issues with my alts.
I am learning ALOT about my alters through these exchanges and even though I hate the fact that I can't remember most of the conversation in the morning, it helps to know more about my selves.