No they are not that smart, however, it is important that you do it at night in the dark, and that the chicks are not too old. If the chicks are a little cold, they will be peeping madly, and actively seeking the warmest spot which is under the hen. I have dropped them on her back, to have them slip away underneath. There is an amazing amount of space under a broody hen. I think it works best with a hen that has been sitting about 2-3 weeks. Get them in there, and then do the hardest thing, LEAVE THEM ALONE. It can be hard to leave, but you will just either cause distraction and upset the hen, which can cause it not to take.
