Sounds like the decline in cell size as you go from the middle of the hive to the back was associated with their wish to cluster there?  I can see that we could all have fun - once we have some empty TBHs or foundationless comb - re-arranging combs according to cell size to see if we can produce brood nests better than the bees, then perhaps lobbing in swarms and watching what happens?

Why not, as a first step, lob (a Scottish term?) swarms into hives fitted with frames with shallow, preferably unembossed, starter strips and watching what happens for a full season until maybe swarming time comes close again?  If enough of us do it we may discover something interesting and useful, or not.

 

Chris

(thinking bees do nothing invariably)