We could add a few more rules into the pot. I saw a somewhat dodgy documentary about how to survive a plane crash. It claimed that non-car users and those travelling alone have better than average chances.

Apparently car users get confused by seat belts in an emergency and tend to try and release themselves the same as they would in a car - ie by pushing something rather than lifting the buckle. I can believe this... I've often seen frustrated pax unable to work out how to open the thing.

People travelling alone tend to be focused on their escape and survival. Those with family help each other and end up delaying each other (so its claimed).

So perhaps those in the exit seat should be non-car using lone travellers. At the right time they will be able to get out of their seat and focus on opening the door.