I never had any great probs in my 100 or so hives , having almost one nuc box for each hive allows a simple reproduction of a queen and proven fertility . Slipping the nuc's egg filled & sealed combs into the hive it came from and taking out the six frames that were either not filled with stores & brood was part of th cycle of inspection so not much effort .
Some times I noticed the old queen and snuff her out but most times I just added the nuc's frames & let the hive sort it's self out over a day or so .
If I was after a double brood I put a times news sheet across the bottom QE , poke a few holes in it with my hive tool and sit the top brood box on it with the neu'c frames and some drawn frames then add anothe QE to stop egg laying in the supers .
If a hive was strong I'd often take the QE out , add a super and replace the QE on top to give a QE .
I was often told that Bees generally only swarm if there is not enough space for the queen to lay her eggs because the hive is so full of bees. Not sure if it is true & temperature & humidity related or a pheromone response . In this situation she'd swarm before a new queen cell hatched .
Or They swarm as a result of , if the queen is in serious decline and the hive decided it was time to terminate her and raise a new queen or three etc. then the prime swarming & subsequent diminishing sized swarms would occur if the hive was left unattended .
Come winter I' bring the hives back from the field and unite two broods into one hive again using the paper method then use " Ceretain " ( sp ) to stink the hive & my blower to drive bees down from the top brood box a few days later .
Once the cleanse was done I'd put the freed up combs in a special made case that would hold 24 brood combs ( it was fitted with four bee escapes ) & leave it by the sorted hive on the honey barrow .
It soon became evident if the queen remained in the frames in the clearing box as the bees would cluster all over it. Most times I got it right first time , but if I'd got it wrong it was a simple case of changing the frames over back into the brood box & rebuild the hive again .
In the meantime I would usually be working other hives in the wintering apairy.
My feeding regime was industrial ...with a 3 inch deep sealed ..hopefully leak proof tray feeder with a central 19 mm feed access hole on each hive . They at sat on the supers or brood box with a crown board on top that had four bee escapes in it . Pumping a modified sugar solution in the feeders via a hose from th liquid sugar tank on the bee trailer .
I was told by many of the smaller keepers that I'd started to feed too early, often in the first fortnight of August if the nectar & pollen was scarce .
Very few of my hives died from over winter starvation trailer or because the cluster was too small to keep heat enough to move around the frames for stores.