Just how are you gonna get rid of a hornets nest without destroying it?
Sure knocking the nest from its perch will anger the hornets and cause them to swarm in your direction...But after a short and decisive battle, which the hornets always lose, you are rid of both the hornets and their nest. Oh sure, maybe they'll move to your neighbors house and set up a new nest, but that's his problem: If he wants to live with hornets then that's his choice.
One thing is certain: I would rather be stung in the heat of battle with the hornets rather than at some other time when I am least expecting it.
Scott Evil
P.S. I just got stung by a Yellow Jacket a few days ago...Damn that hurt! But the Yellow Jacket has assumed room temperature and that made the pain a little easier to take.