Memory in Multiple Personality has Advantages

Most people do not want to remember every trivial detail of what happens in their everyday life. They want to remember what is useful to remember. A good memory is one that forgets trivia and remembers what is important.

However, in multiple personality, there are separate memory banks for each personality. So it would be practical to have a personality that did remember seemingly trivial details. You could even have a personality who remembered things that never happened, fantasies, because other personalities would be grounded in reality. True, some personalities would have memory gaps for times that other personalities were in control, but the latter would recall what happened.