Sorry if this is a major debate and I just sparked another bonfire....but I haven't seen any posts on this particular yet.

I thought the major benefits to TBHs were 1) calmer bees, because you don't expose more than 1 bar at a time, but Warre hives don't appear to have this feature, since the bees have to be able to travel vertically. 2) With horizontal TBHs, you don't have to lift anything.

Besides providing insulation at the top (which you could do with an extra super on a Lang) and putting new boxes under the old (which you could also do with a Lang), how is a Warre different from using foundationless bars (with or without a frame, I'm not sure the bees care) in a Lang hive?