I have thought of taking a video, to show just how well it works with a broody hen. Mine set in the coop, and hatched them out there. After 24 hour, she left the nest, and created a nest on the floor, with all the chicks under her.
For the first two days, I got up pretty quickly, and let the layers out to free range, just to give everyone some more space. But I have been watching them, and they are just pretty much part of the flock. For the most part, the broody keeps the layers on one side of her, and the chicks behind her. I do have hideouts, but none have really been used.
When I free range them, the broody and chicks keep more to themselves, and stay a little closer to the coop. But not much, the broody has them crawling up banks, over sticks and branches, they really get their exercise!
It works much better than doing the whole fence, separation thing for me.
I have seen much advice of separating the broody hen from the flock, but I am not a believer, when those eggs first hatch, the hormones are strong, and the broody hen, would take your arm off at the elbo, that aggression straightens up any of the layers into leaving the chicks alone, and by the time that wears off, the flock is used to them.
MrsK