It's an "Automatic Hive" as used by Oscar Perone in Argentina - complete "leave alone" beekeeping - honey is harvested once a year, apart from that, no interference at all. Apparently large quantities of honey are produced, and they have no disease problems.... In short, the theory is that the large undisturbed brood nest enables the colony to grow to an optimum size, which allows them to become a very large and thriving entity that can deal with anything nature can throw at them in the way of disease, mites etc
http://www.naturalbeekeepingalliance.com/