Will reversing hive bodies really help swarm prevention
it will certainly slow down and confuse your bees. i have no idea why anyone ever thought this was a good idea.
opening the brood nest, splitting the hive, etc. are ways to
maybe prevent a swarm. some hives will just do it no matter what. search here for swarm prevention ideas and look at robo and Michael Bushs' sites. they both have good stuff.
bees are driven to swarm in the spring because it's how they increase numbers in the great outdoors. it doesn't usually have much to do with how much they are bringing in this early. watch for swarm cells and consider making nucs, or splitting if you need to.
i have had to super early when i was going to be out of town. as long as it's warm enough that they are active, giving them the room will not hurt them. if i am home, i watch for them to store honey over the brood nest. once they have started doing that, i super them.