I have read many chicken raising books, so I don't know which one I read this in, but it made good sense to me. I read that you should only breed young pullets with a mature, calm rooster. An immature physically young pullet who just started laying, in her first cycle of being bred, can be injured and even killed by a young rooster that is just learning to deal with his raging hormones. This is even if the rooster was raised with the pullets. So, if you have a young cockerel, you are supposed to put him with a mature hen, who will be sexually mature, that has been bred the prior season and will only take so much off the randy young rooster before putting him in his place. The mature rooster will be gentler with the younger pullets.
I think the best place to find the mature rooster and a mature hen for the young cockerel would be swap meets. That's what I plan to do. I also belong to a poultry club (organized and run by Pat Foreman, author of Chicken Tractor, Day Range Poultry, City Chicks, etc.) so I will most likely be able to purchase mature roosters and maybe a mature hen to get my new-this-year chicken flock off the ground without harm to my young girls. By next year, I am hoping to get all my chicks the natural way with a broody hen.