@ patrick I don't keep nationals any longer and local keepers are extreme hobbyists, so I have no direct references. It does matter what others think because adoption is actually key. Tanks were largely ignored when introduced. Thermal properties of trees are not critical as values to achieve in hives but in understanding bee adaptations and how we have morphed their behavior out of their optimum. Given that bees live in a range of places, including underground, it is widely accepted that their primary habitat is holes in living trees. If I told you that tree trunks follow the ambient temperature very closely (leaves not so - from tundra to tropics, leaf temperature is always 21 degrees because that is what chloroplasts operate at) with little time lag up to an absolute maximum of 34.5 degrees centigrade at which point all stomata are opened to prevent it ever going higher. Not coincidentally, this is the exact temperature of a brood nest, so it follows that bee hive cooling behavior is a novel adaptation to thin little boxes. I am sure you can see the implications of this for workforce deployment etc naturally vs a box. Further, a tree core temperature drops to about 0.1 degree above freezing and never below. So it follows that all our understanding of the winter cluster are the studies of largely novel behavior, and breeding for ruggedness is like trying to breed woolly mammoths out of African elephants - in just 150 years. Because before boxes, skep keeping was based on catching wild swarms and destructive at season end, with no need for overwintering. Further, I believe there is a very important acoustic element to nest selection. A conventional hive is rather like asking a Trappist monk to live inside a banjo. Everything about hive design follows from this. Follows, because as a beekeeper you know very well that we follow our bees, that they lead, so we should look at and try to follow their adaptive preferences also. And being nature with millions of years of honing behind it, it is actually very simple.
@ Steve It sound like you had a wild year but a good crop. Re the hive: insulation is really obvious and there have been many long and very large academic studies of it , but they have always hit 2 perennial problems - condensation and constipation. It isn't actually very good for bees, even though it is better than none. Condensation: High atmospheric water has a host of issues, from rotting pollen to nosema and other respiratory fungal issues, to rotting hives, fermenting stores, etc. Of course, the fibrous inside of a tree hole has no such problem. Constipation: In a well insulated conventional hive it takes about 8-13 hours for the ambient temperature to communicate itself to the bees by penetrating the hive body. This lag is not soon enough to signal to them conditions for an excretion flight given short winter days. So they don't leave for months, causing crapping problems. In a tree which moves with the outside temperature, no matter how up inside a trunk, bees will know it is reaching 12 degrees and a shite-flight is on the cards, almost in real time. And just to irritate some, mesh floors are not found in nature. The bottom of the hive is as important as the sides and top.
My work has been towards solving these problems and a number of others along the way based on a national brood frame. Double to 2.5 brood base and brood sized supers. The hive also changes the colony and brood structure so that understanding why swarming happens is quite obvious and a simple technique that prevents the right conditions being met almost completely eliminates it.
Cheap and quick build is important. I've done that. But I don't think they would be accepted because of the large amount of experience and skill invested in ones existing gear that has to be let go. Not realistic to expect. It is a new generation keeper thing, maybe.