In my experience, here's how to prevent an aggressive cockerel: get rid of every male who shows inclination to attack a human, and breed the ones that don't.
I had an aggressive cockerel or two in the early days, didn't breed them, bred the boys that never threatened a human, haven't had an aggressive cockerel since. It appears predominantly genetic in basis. If can be bred out, but it takes generations of work, and I can't be bothered when there are so many non aggressive roosters out there to breed from instead.
Having said that, it really helps to not be afraid of your animals, as fear reads as unpredictability to many animals and they will try to remove the perceived threat, and it also helps to never take a male from someone who breeds human aggressive animals. I've had hundreds of chickens, half of which were male, roaming the houseyard and house paddock with small children for years, and never had an issue --- once I learned what a good rooster looked like, and what the warning signs are. And of course all that stuff about familial inclinations, lol.
I don't stop them mating, because only another rooster (or sometimes a hen) needs to do that, and any chicken stupid enough to think a human is a chicken is too stupid to breed in my opinion. Not only that, in my experience it's likelier to be sexually attracted to humans since it's species-confused as well.
Chickens are smart enough to recognize dogs, cats, horses etc aren't chickens, so I'm pretty sure most are also able to realize we are not chickens either. The majority of chickens can even tell their own species apart from other avians.
My males have never had a problem respecting humans despite being handled and let to breed unmolested so that's not a prerequisite for respect. The whole "stop the males from mating like you're a dominant rooster" thing would only work with either males who are already respectful, or species confused males, and at the end of the day it's up to you to find what method works for you. No one method is the only one that works.
I also handle the males, as well. It's a livestock animal, just like the females are, if it needs tending it'd better be tame enough to make a patient I can help as opposed to one that can't cope with being handled, or won't tolerate it, and it needs to be safe, for the sake of the children. Otherwise it's a waste of my time and money.
Also, I will not live in fear of my own animals. Or anyone else's. Australia's livestock industry has lost patience with dangerous males and none of the commercial "big players" bother with dangerous males (or females) of any species; they're a waste of money and time. People used to think that aggressive males were the better ones, but research in the cattle industry found positive correlations between excess aggression and low fertility, and certainly that's been my experience as well with males of all species I've kept. The theory favored is that the testosterone isn't being utilized by the system correctly so it results in lower fertility and higher aggression. Some aggression in both genders is normal and natural but after thousands of years of domestication, I'd be willing to bet that the only remaining human aggression in them is due to breeders who thought it was a preferred masculine trait or otherwise encouraged it, through bad or lackadaisical breeding, or unnecessary interference such as using solely artificial insemination generation after generation so the animals sexually identify with humans rather than their own kind.
Just my 5 cent's worth, lol, but whatever method works for you is fine, as long as you're not likely to sell me a human aggressive rooster that goes and kills some child, I have no issue with it. Best wishes to everyone, whatever your preferred method is, whether we agree or disagree. Hope your rooster doesn't turn, Johnn.
