I'm going out on a limb here but I'm thinking your methods of hand rearing cockerels may be far different then some of these others.
I think they are raising them more like it's a child. Holding and carrying them in their arms like a baby. Lots of hugs, kisses, snuggles, whispering sweet nothings in their ears, etc.
Maybe I'm wrong but not picturing you doing quite the same as some of these younger girls/women are doing.
If I am wrong I apologize and think we would all love to see a video.
FOUR WAYS CHICKS HAVE BEEN RAISED BY ME
I am into behavior so imprinting is particularly interesting. Some of this I am trying to manipulate to improve my rearing efforts. Some rules followed here but not mentioned may be violated by some parties hand-rearing and brooder-rearing chicks that may cause troubles later.
Brooder-Raised
Chicks reared in brooder imprinting only on other chicks. They can sometimes be afraid of you although they can overcome the fear when food or water is involved.
Hand-Raised
Chicks reared in brooder although imprinted on you as well as each other. Imprinted chicks will follow you like they follow hen even when now food involved. Interactions involving physical contact between me and young birds are much more frequent and often involve allopreaning. This takes a lot of time out of your schedule to do.
Hen-Raised
Hen only participates in rearing chicks. All parties (chicks and hen) imprinted in each other. Once chicks weaned from hen, they have only each other. This system occurs when hen rooster ratio is high. Chicks generally scared of me unless hen brings them to me a few times for eats. Most I currently raise in this manner and almost all my hens bring broods to me.
Harem-Raised
Hen provides virtually all nurturing during first five weeks although rooster provides tidbits and limited protection from predators. During this time rooster and chicks bond on each other and process seems to occur when rooster puts his head down among chicks as they forage together. With respect to ground predators, rooster will get loud and stand in open as hen slinks of with chicks, when predator distracted rooster goes for cover as well. With some ground predators, rooster will assist hen in attacking it and occasionally can surprise something like a fox or young dog. With respect to hawks (Coopers in particular), the rooster is the front line defense while hen largely tries to cover chicks up. I have seen hawk-rooster interaction multiple times in games but not yet with American Dominiques where chicks are involved. Parental game rooster acts like a broody hen when dealing with threats and does it only for chicks of his harem. When hen weans chicks as they become juveniles, the rooster then takes over brood care as hen starts another clutch. The rooster then has juveniles with him until they are pushing 12 weeks old. He provides protection from predators during that time as well. Some roosters during first few weeks will actually brood during rain events or when weather cold. The rooster also very important in getting juveniles to roost up if the hen has not completed or started the process. At some point after 12 weeks, the rooster boots offspring from harem or at least they drift off during day. This system occurs when hen rooster ratio is low. Subsequent interactions between me and chicks follows same pattern as with hen-raised broods.
Each year; I brooder-raise, hen-raise, hand-raise and harem-raise roosters. Rearing method itself does appear to be factor impacting aggression, nor does confinement by itself as free-range also used. Particular events the rooster remembers do appear to play a role. The particular events jibe better with each rooster being different even when of similar genetic background.