I think people are onto something with the water treatment. The bubble bath and the spray bottle and the garden hose.
I read years ago that parrot handlers use water to stop parrots from biting. When the big parrots bite, I guess they don't let go, so the handler walks over to the kitchen sink, turns the water on full, and holds hand with parrot attached to it, under the water. The parrots hate the water, they don't bite anymore.
I thought what a great solution! Its non-violent! And I've found water to be very effective - first with a spray bottle for keeping the cat off the table/kitchen counters. Works great on cane spiders - who are too fast to catch and usually up high on the ceiling, but within the reach of the spray bottle set on "stream". Also worked on our angus heifer we had to mow the lawn - she took up bawling one day out of boredom, so I turned the hose on her right after a bawl. Four bawls, four sprays, and she looked at me and got it and no more bawling. I was surprised it worked - the water did not hurt or anything.
I think much of rooster behaviour is set by hormones/instincts/genetic personality traits. I've had several that looked demented after they came of age, and I didn't keep them. The scariest one, a Blue Andalusian, made a blowing/hissing sound coming at me slow and low and deadly.
Another help for me was reading about horse whispering - how animals have a body language, and people learning it don't have to get so violent to train. Like with horses, merely kicking ones leg at them from a distance says you are dominant. It is the gesture that communicates. One never has to connect the kick to the horse. All it takes - and don't back away or step to the side when a horse approaches, always make them gave way their space. This one piece of knowledge totally changed my experience with horses. Much more to it also.
I do the same with roosters - make them give way to my space, never move over for them, grab and hold them on the ground while holding their neck and head to the ground until they relax and stop fighting - the relaxing of their body is their saying "uncle" to your dominence.
Also someone said he never lets a rooster mount a hen in his presence. The alpha rooster never lets subordinate roosters mount a hen in his presence.