This would be a good experiment for all that don't know the benefits of wrapping to try. If you don't have tar paper available, hit some homebuilding dumpsters and see if you can't find enough. Wrap 1-2 hives, leave an empty super above the inner cover in case you want to feed throughout fall, or winter, or spring. Compare in the spring. Depending on your area and severity of the winds it will be a good experiment. If you have wind, rain and no sun all winter, there probably is not much solar gain to be gained, so to speak. If it's sunny and marginal temperatures you may be surprised.
Those that say the bee's have been managing winters on their own for millions of years have forgotten some of the newly man made stresses, ie., mites, pesticides, etc.. I'm of the mind if this helps at a minimal cost of labor and materials I'm interested. Just an idea.