According to this website on dissociation which is in my signature, the definitive boundary line between DID and other dissociative conditions and OSDD is "true amnesia"...missing time.

My take off is...

Dissociative amnesia is where you don't remember the traumatic event...it's blocked from your conscience.

With DID, you like have missing time, holes in your timeline, regardless which alter you are at the moment.

It's like, it was Monday, now it's Wednesday. It was 2009, now it's 2013.

It's not like losing your keys, or more you came too and find that you are at work 4 hours later, or talking to someone and realizing that you just got there...

What you did this morning and yesterday is like...I don't know, I wasn't there.

You only remember a few hours yesterday, depending on who is up front.

Oh, I love this one..."what's your birth date...ummmm, hang on...[I'll be right back...come on guys]..."

I hope this helps someone from an affected individual get some sense of definition.