Severance

Importantly, up until this point innie-Mark has pretty much always done what would benefit, or at least not disrupt, outie-Mark. This is the first time he's done something purely for himself, knowing it isn't what his outie wants. Even if it's doomed, it's his only taste of independence.

For all intents and purposes, they are the same Mark. But, self-liberation starts within, with your inner self. If outie-Mark is going to truly be free, innie-Mark needs to be the one to claim that freedom for Mark’s holistic self.