1) i would say like just like you know you love your wife. i mean..in a way.
actualy, when they want to swarm,the queen wants to swarm, and she lays eggs into the queen cells, and she leaves (usually) before her daughter emerges. but when there's a supercedure going on..i would say bees "tell" the queen they're not happy with her, and that she has to leave the new queen emerge. i mean..it has all to do with pheromones.
2) i think that they will kill in cell if possible, but if the emerge right after her..they have to fight, and while they're fighting another one emerges...that's what i'd say
3) i answere this in the first question, the queen wants to leave, and wants her primary hive to survive.
but all of this things can go bad, and i think that no one knows why. sometimes a supercedure can end up in a swarm, or a swarm ends up in (i think) up to 7 swarms, of course they higher the number the smaller the swarm, i have heard of...4 swarms, so..i'm not sure about 7.
a hive is run by bees, not by queenbee and not by workerbees, but by BEES, ALL of them, a hive is 1, super-organism is the right term.