A few months ago I told my T that mindfulness was just like dissociation. She didn't get it. But to me it's like you stop thinking about everything that came before and only focus on the present moment. For some alters that's exactly what they have always done. It's how we live. We never think about what came before this present moment of consciousness. It didn't exist. All that exists is this present moment, right now.
When our T was trying to teach us mindfulness it was like, well duh, that's exactly what we always do. I think for people who dissociate re-associating is the harder skill.