I have always did the oppsote I take the DOminant chicken and put it in with the Pullets, and a couple days later the next dominant, and after a few are acclimated totall Clean out and refesh the Coop maybe rearrange the roosts, change pen size and wear water and food is.. etc. and then bring all birds into the new and refreshed coop and pen, the new ones are disoriented and its like none know who is what and normall goes without a bad peck.. I am sure the others work also just how I have done it and will be doing it with My new pullets in a few weeks Expanding the pen double in size.... its like no one has a territory to fight anymore they think they are all in a new house...
Good luck to all
Good luck to all