I made a ventilation box from Tarheit's design (thanks!) and seems to be going well; no comb in it either! Anyway, it has an entrance in front. The ventilation super is on top of two honey supers and there's always a hand-sized patch of bees washboarding around that upper entrance, but no arrivals or departures for foragers at all that I've ever seen. The occasional drone uses it, but that's all. The regular entrance below, reduced to about 4", is where all the coming and going happens. Is this odd?