Plan B - how to catch bees

Bees swarm. If it's a primary swarm around 10,000 bees pour out of the hive together with the queen and take to the skies, but not for long. They normally fly just a few minutes before resting on a nearby tree or wall. Then they hang in a big cluster and wait ... and debate ... for hours ... sometimes days .... until all 10,000 reach agreement on where they are going and how they are going to get there!
You would think a more sensible approach to moving home would be to agree all this before leaving the hive, but the old foragers are too set in their ways and the baby bees are too young to fly, making sensible discussion of relocation plans nigh on impossible.
So instead all those in favour of relocation leave in a swarm and then hang together somewhere trying to agree where they are going to live.
Fortunately not all the bees have a des res in mind otherwise they would never reach agreement. Instead dedicated scout bees scour the neighbourhood looking for a suitable home. This process probably starts days before the colony actually swarms, but nobody pays attention. Now the bees are homeless they are eager to learn what the scouts have found, and slowly, as more scouts return with enthusiastic reports about a potential new home, the bees reach a consensus.
Ideally, bees want a dry, airy cavity above the ground. If it has previously been occupied by bees, even better - which leads me to Plan B - Bait hives.
By placing empty hives containing old honeycomb around the locale beekeepers can reasonably expect to catch a swarm of bees. 'Catch' is a bit of an exaggeration because the bees simply walk in; one moment the hive is empty, the next moment thousands of bees have taken up residence.
I'm excited. My bee-buddy tells me one of my bait hives has hundreds of bees buzzing around the entrance. This could be it, more bees at last....