One could combine the fuselages together, getting rid of dozens of windows, several doors, the surface drag of the inboard fuselage surfaces & wing roots, move the engines outboard....I would then suggest calling this proposed simplification of Airbus's patent a "widebody" airliner.
It would be interesting to watch the people colliding with each other as part of each fuselage "evacs" inboard an emergency. Or of the gear is torn off, those evacuating into the center being trapped. Why have doors towards the middle?
I would want to sit in the fuselage with the cockpit/pilots in it....If they're looking for something "soft" to hit, wouldn't want to be in the other fuselage.