Hen's don't have fans underneath them either, lol. I wouldn't do this in my Nurture Right or IncuView because the fans are cranking, though I might be more willing to try it in the still air Little Giant I used to have, or the Hovabator even with the fan maybe. The relative humidity when you don't have an actual heat element drying out the air is usually higher in general, plus the moisture coming off of the broody. We're basically just trying to imitate nature to the best of our ability with styrofoam, plastic, and aiming hatching vibes at the incubators. lol