I'd say interesting rather than dumb


I don't have any concrete "fact" to offer up in reply, but thoughts similar to your own were part of why I switched to 14x12 brood boxes this season. I don't personally like leaving supers on hives for a number of reasons and I thought that for my bees that a standard national was a bit small as I ended up with a lot of pollen in the first super which suggested to me that a national wasn't big enough to accommodate a natural brood nest, where I am and with my bees at least.

I wanted to be able to take off honey without having to feed syrup to the bees and so far my impression is that a 14x12 gives the bees the space they need, in a single box, to raise brood and store sufficient pollen and honey that I can regard the supers as being mine. I guess that means that I probably disagree with you that a brood box should be smaller than a current national, if only because I think (without any evidence whatsoever) that the fewer obstacles the cluster has to negotiate to get to stores the better.

Perhaps your question about the cluster moving through winter ties in nicely with a thread about frame orientation on the BBKA site.