for many people it is exclusive. I know many people with DID including my own system before I was integrated that did not have alters that had to pretend in the way your system does. in mine and these others that I know the two issues are mutually exclusive.

none of my alters pretended to be me
none of my alters pretended to be a different alter
none of my alters pretended to have a different sounding voice then what was their own.

each of my alters had their own way of being, their own jobs, purposes. reasons for being, what they did, where they fit in and all these other issues to that are now called sense of agency here in america.

if you read some of the past posts here in the dissociative disorders forum you will find that there are in fact many people with DID who have the kind of system that does not use any form of pretending.

dont get me wrong Im glad you have a versatile system, but many do not.