I like using an incubator for the incubating part, but then sneaking eggs under a broody the night after they hatch. I have had some broodies accidentally crush eggs in the process of hatching, killing the chick. It was like once the eggs were weakened by a pip, they collapsed. And it didn't happen just once, it happened to several broodies. Some were pure marans eggs, ultra thick and strong, and even they got squashed. Maybe I had stupid broodies who smooshed themselves tightly against he eggs...
But they do make fantastic mothers and always accept the chicks I offer them.
Raz, when it comes to hatch time, at lockdown, I lay all eggs on their sides and don't confine them with rails. I find chicks seem to have an easier time hatching on their sides, rather than big end up. The first to hatch will play soccer with the other eggs, but it just seems to stimulate the others to hatch faster! I also have learned not to interfere, as hard as it is. The last critter I helped hatch, a duckling, died a few days later. It would have died during hatch, so I guess it just wasn't a strong duckling.