First, take a look at his plans for the gabled roof. That one seems pretty well insulated. I do need to go back and look at "Smile" and see what Fedor is doing in the appendix where he shows how he makes a hive. But I fully agree that both in terms of heat in the summer (My Major Concern) and cold in the winter, that top needs to be seriously insulated. This also raises the concern of using 2x10 flat with an R value of about 1 is barely better than a regular single thickness langstroth box, especially if you wrapped it in a layer of the the thin green foam board you would get R4 and if you used the thicker stuff even more so. Hey, someone was recently talking about insulating the bottom from the stand. Not sure if that was here or one of the other places.
I have some concerns and serious misgivings about some things from Dr Leo. Unfortunately, he doesn't return my emails so they go unanswered. I can forgive both GdL and Fedor L. because they are dead.

Dr. Leo, should reply to an email. But that is just my opinion. That said, GdL was an apiculturalist. He believed and taught and wrote about the latest cutting edge scientific breakthroughs of which were known in the late 19th century. So I would certainly expect to see him writing about feedings and every other treatment and breakthrough and aspect of animal husbandry and farming that was known. Dr Leo is more of a "hippy". His PhD is in forestry. Here is his CV.
University of Missouri
PhD (Forestry)
Indiana University
Master’s (Natural Resources)
HEC Business School, Paris
Business Management Program
MGIMO University, Moscow
Bachelor (International Economics)
So his agenda is the "natural" or what we are all calling "treatment free" beekeeping. No feeding sugar, no chemicals, no medicines, no homeopathic treatments. Basically, let them do what they want, and catch a lot of swarms.
Don't get me wrong. I love GdL,and Fedor Lazutin, and LL Langstroth. These are the giants upon whose shoulders we rise. But we also have the people of our time like Palmer, and Seely and a whole bunch more that I just associate with YouTube. The jury is still out for me on Dr Leo. I am not sure he isn't just a person with books and speaking engagements, and now equipment to sell. He is selling the sizzle, but is there any steak there? I would love to simply follow the steps in GdL's book and Fl's book and walk away from the hive and come back in the fall and take my rent honey and not look at them again until the spring. And have them be there year to year and not have to do any intervention. That is a wonderful pipe dream. I am not really naive enough to believe it, but wouldn't it be nice. The bee population is way down. I can walk barefoot through clover any time I choose and no one is there to sting me. Certainly not something I could do as a kid. There are microplastics in everything including all our food and our bodies. The idea that hormone affecting chemicals can be GAAS and have no effect whatsoever on bees is amazing that we accept such things.
We are not in the 19th century with GdL. But FL just died about 6 years ago. So we aren't far from his world, except for the location.
When I was first on the internet back in the late 1980's there were forums, but we called them news groups and the feedback time was not nearly as snappy as what we have here. But one of my interests was woodworking and I found the woodworking forum called "rec.woodworking". There were two camps of people back then that would get into flame wars over whether what you were doing was really woodworking if you used power tools. The were not-so-lovingly referred to as Neanderthals and their hero was Roy Underhill who had a TV show called the Woodwright Shop. Whom I love! His writing and way of speaking is amazingly comforting and as a historian he is brilliant. (His daughter is quite the accomplished musician as well, but I digress). The other side of the fight were the power tool users and always seemed to believe if you can get a better tool you could be a better woodworker. And they all seemed to love Norm Abrams and were referred to as Normites, by the Neanderthals. the flamewars, though entertaining to watch accomplished nothing. There was a term for the rest of us and that was hybrid woodworkers. We use the tools we have, or the tools we prefer to do the project that makes us happy and it is still woodworking no matter what any one else says. So some days you pull out the hand saw or the chisel, and other days you grab the kreg pocket hole jig and reach for your festool whatever and so on and so forth. Ultimately we all are walking our paths, and hopefully we can get something good from each of these folks that went before, and are going now. So I want to be that same kind of beekeeper as I am a woodworker. When I do cabinetry, I use every power tool I have. And when I am making cigar box guitars I spend hours hand sanding and hand cutting frets. Same with the bees, if they need something to eat, I think I am going to have to give it to them. If they are being murdered by some kind of parasite, I may just have to fight back with some kind of treatment. Somewhere between hands off and all hands on deck should be a happy medium. That's where I want to be.