This is something that is really bothering me.
I've studied the science of applied behavior analysis, and would be horrified if some of my instructors were ever to witness my interaction with this rooster.
Have any of them ever trained animals? Is it possible that you could pose them a hypothetical or real challenge here and see if they can come up with anything?
While what you're doing here is just following the standard last-ditch attempt at stopping the behavior, and there's plenty of people who recommend it, to the best of my knowledge nobody who has had it work permanently. I may be wrong, and surely there are some examples out there of a rooster who learnt his lesson the first time, and for all time, statistically speaking it must have occurred. But there's an awful lot of people who have tried it and had it fail, either way, which is not a good place for you to end up in, abusing then killing an animal if/when it fails to reform them. While you're only using the same 'communications' another rooster would, if it's abuse to you then that's something you'll have to live with and if it's not sitting well on your conscience, it's potentially harming you... Sounds weird maybe... But doing things we believe are wrong are detrimental to us, I believe.
If this is distressing you, stopping would be a wise idea, I think. There are nonviolent roosters out there, you don't need to go through this. Violence can escalate to the death of one of you, or permanent maiming or disfiguring; the rooster who attacked me first went for the face, from the ground he just leapt, didn't need to fly. That's a heck of a leap; luckily he didn't get to harm me, but it was close. He was never abused. He gave no warning. The only warning was in the fact that he came from human-aggressive stock and had shown excessive aggression to other poultry. If you're worried he will harm you, be done with him, please, it's a very legitimate threat. If you can't cull him yourself, no shame in that, someone would be glad to take him, and if you tried you may be able to find him a non-culling home, or at least one who will try to be such, but, I don't think he's worth it.
I did a couple of week-long workshops with the trainer who puts on the bird show at Orlando, Florida, for Disney's Animal Kingdom. He's a world renowned trainer who consults all over the world. The workshops were geared to parrot owners, and aggression is always an issue with parrots, especially male parrots.
His philosophy is if a show bird shows aggression to him he will never work with the bird again. Others can often work with the bird, but he will not. He is making that decision because once started, aggression continues and escalates. I was shocked that one of the world's top animal trainers could not or would not train aggression out of one of his show birds.
I think he's very right, and many animal trainers/breeders with quite illustrious proven track records, i.e. great working dog breeders and trainers, say the exact same thing. Same thing with those who train (and usually also breed) cattle, horses, etc, people who are famous for their ability to train animals tend to take a very strong stance against the violent animals; if a bull who rarely interacts with humans doesn't get an excuse pass for anything other than 'quiet' behavior, why does a rooster who has absolutely no fear of humans?
I too was originally one of those who thought to give the animal another chance, try everything before you give up. I have since learned it's not worth it; animals have their own minds, make their own choices, if they choose to be a certain way you will have to either let them be that way, or force them to stop somehow, and the forcing often descends into abuse because the animal is not willing and that leaves no other options --- not that abuse is much of a real option anyway. I too used to think it was too 'easy' or a 'quick fix' when people would just put animals down for violence, but my experiences have taken me a full circle to sharing their viewpoint.
The world's best producers of the finest working dogs, very experienced trainers and breeders, waste absolutely no time on dogs which show certain subtle negative traits, from puppyhood onwards, they simply get rid of them. The traits are very, very strong. You shouldn't have to work against its nature. It's either willing, or it's not. These people of all people are in ideal positions of knowledge, resources, and experience to train or manage the behavior --- but they simply refuse to. They've all got decades of experience behind that decision, and personally I bet they don't want to waste the rest of their lifetimes struggling to manage a few unwilling or aggressive animals when they could be devoting their time to great animals instead. I'd also bet they devoted time to the challenge of trying to make it work with aggressive animals, and gave it up as pointless.
Many animals are so anti-human, or so aggressively bent mentally, that you cannot train it out of them; training depends on the animal's cooperation to be successful, it's not some kind of straightjacket you wrestle them into, so if they're not willing, what can you do? Their violence is very often independent of cause or provocation, or their perception of provocation is not able to be amended. It's very often also independent of abuse, the nastiest animals I know have all been well-kept, sometimes spoiled which arguably is often detrimental, but many of them have been treated correctly in all ways. No abuse, well trained, well socialized, well kept, nothing lacking from the picture-perfect life the best of our knowledge prescribes for that species.
The majority of those to whom aggression is unacceptable cull it out, not attempt to manage it. The rest breed it on because they either believe it's inevitable, manageable, acceptable, or they like it as someone mentioned, some cultures value human-aggression and extreme violence in their males so select for those traits; Spanish bulls of the bullfighting breed are a good example. There's a judge on this forum who has stated that they like human-aggressive Games, too, and plenty of others who expect or value human aggression, and select for it by discarding males who aren't 'feisty' enough.
I haven't had chickens long and this is my first experience with roosters. I am partly to blame because I misunderstood some early aggressive behavior (I thought he was tit-bitting for me, silly me).
You really shouldn't blame yourself. It's incredibly unlikely to be your fault. Misunderstanding his tid-bitting makes no difference. If you had understood it, it still would make no difference to the outcome that I can think of. What reaction could you have made to change his mind about attacking you?
He didn't do that to communicate with you anything other than a threat. It was not an attempt to open a dialogue so to speak. It was one-sided, a warning, the foregone decision had already occurred in his mind; it was part of his pre-attack behavior. Roosters who do this are already approaching an intended victim and I've never seen it have anything to do with what the victim was doing --- in almost all cases the victim was minding their own business, not near other chooks. In the rest of the cases it was two roosters approaching one another and fake-tid-bitting with a view to fight. It's not a reaction to provocation other than if you're going to class your very existence as being provocation to the animal, which, for some, it definitely is. Chances are extremely high that his mindset was always operating in this way, viewing you as a future opponent.
Good roosters never fake tid-bit to humans like that; the fact that he would is serious, proof his mindset is unsafe. I've never seen a rooster change his mind once he's started that fake tid-bitting to an intended victim or opponent.
Threats and aggression towards humans are not automatic nor inherent behaviors of all roosters, just like cannibalism is not an inherent nor automatic behavior of all chickens; this is one of the biggest and most common misapprehensions about them, I believe. Some will, some won't; it is not a behavior all will exhibit 'given the right circumstances'.
Some will cannibalize even when not hungry, some will starve to death rather than cannibalize. Some will attack without ever having been abused, others will tolerate any amount of abuse and not attack.
There have been some studies conducted testing the efficacy of breeding traits like cannibalism and violence in and out of birds within around 7 generations, which I was always told is the average time it takes to remove or introduce a trait reliably, and I have always found that's true; the studies proved it was remarkably achievable.
My chooks don't react to red or other colors on people. Other people's chickens will attack them when they see those colors, as noted in some other posts. They're probably also likely to commit cannibalism if the sight of red inspires rabid pecking. Again, this isn't how all chickens are. Neither red, nor protein deficiency, are the actual triggers of cannibalism, it was an underlying trait that was always present in the bird that exhibits it. I'm defining cannibalism here as that committed on living birds not for example in the case of a chook who lives outside a processing plant where perhaps chicken guts are thrown around and left. Attacking and consuming another living chicken is not the same thing.
I've gotten chooks from some far-out places, and some very bad ones too; one place I got about a dozen birds from turned out to be a meth dealer's place. Those birds were absolutely hysterically terrified of people, and had been abused. Not one bird of that whole varied group has produced a violent descendant, though surely of all my flock they had the most reason, they'd been kept for many generations in that place.
I also got about a dozen birds from a lady who never abused her animals, but who tolerated them abusing her, and these ones were of course human-aggressive and so were their descendants for a good few generations. The 'cause' is irrelevant if the animal chooses not to attack. It's the animal's response, their choice, that is the actual cause of the violence. People understand not victim-blaming among human society yet many think it's all justified in animal society, lol... It's very rarely justified and reflects at least as much on the attacker as on the victim, actually more so. Some animals are more likely to attack than others; I believe if the animal can be encouraged to attack it was never that far off it; perhaps its family line was on the receding side of having violence bred out of them, and encouraging the trait by stimulating it in a predisposed bird caused it to resurface --- but the final call on that remains the individual birds' decision. It can be bred out but it's dangerous and time consuming.
Those roosters who gradually descend into attacking people almost always showed some subtle warning signs. A 'jealous' rooster for example is a warning sign in itself. You must be able to handle your flock safely, for their sakes, as well as yours. Any chicken which attacks you or the animal you're holding is a liability. Their offspring are also more likely to attack you.
Your flock either respects you without you doing anything to enforce the respect, or they don't and probably won't, no matter what you do to try to enforce respect. I prefer their trust, positive association and goodwill, not their fear, dislike and distrust. Aggressive animals in my experience are more often that way due to a familial predisposition than what has been done to them. With the smarter animals like dogs you can certainly train many to become aggressive but even then there are many dogs who simply will not become aggressive, not matter how abusive their owners are.
I really appreciate your advice, Chooks4Life.
You're welcome, I hope you find what works for you, whether it's as per my suggestions/experience or contrary to it.
Best wishes.