I agree. In fact,after several years of having chickens raised from mail-order we finally had two girls go broody and let them set eggs. They were in a brooder coop inside the main run so all the hens could see them all day. At 3 weeks we started letting the mommas and chicks out with the rest of the flock and now the older hens are flat out scared of the mommas and chicks! Every time the hens got close to the chicks a momma seriously nailed the hen. After a week of them all being together all the flock gives the chicks plenty of room! Now if a chick wanders to close to a hen....the hen will give the chick a quick peck and things are ok.It has been my experience that the mama will protect them. I have let them roam with the others at 2 weeks of age with no problem. If the other hens come over, mama puffs up like a feathered beachball on legs and let's em have it!!
As a side note,It's amazing how much faster chicks learn to be chickens when there's a momma hen teaching them. We have 15 chicks from Mt Healthy in another brooder coop that are about the same age but way behind in the learning curve! This may be the last year we order chicks...just start raising our own.