If they have enough room to get out from under then it would work ok but I agree there's no point. You'll just waste brooder space and run the risk of them all cramming together along the edges to avoid the light. Use a lower wattage bulb or raise the lamp up. I start with a 100watt for a few days, switch to a 60w for 1-2weeks, then a 40w red bulb for a week, and usually by then they don't need heat since I raise them in the house but sometimes just to transition them easier I stick a 25w blue or red in there until they get used to it being darker.