On my Italian cross hives from southern texas, the bees starved on location without moving two inches to reach stores. They had moved up about half a frame, and thats where they were DONE.
The Carnys, and feral bees seemed to have no issue with COMPLETELY emptying all three medium boxes of every ounce of honey.. irregardless of the extreme conditions this winter.. Despite my dislike of a sheet of plastic between bees in a cluster I have to admit that the frames of plastic I do still have in some hives seemed to make no difference in the survival of the Carniolan and feral stock.
I have no scientific proof, only the observation.. I would like to say that the plastic made a HUGE difference, or that all the boxes with plastic died... But at this point I see not a whit of difference.