I want to add complicate this discussion a bit more. Over generations, and especially (IMO) with so many of our birds grown in hatcheries, where production is most important, and natural behaviors aren't considered, but also when breeder birds anywhere are selected for qualities totally unrelated to what's 'normal' for chickens, aberrations occur.
Sorry, too long a sentence!
Shadrach is raising generations of birds in a more normal flock environment, so extremes in behavior tend to even out or become more manageable. Normal is good!
Newer chicken keepers aren't going to recognize early signs of human aggression, and if birds aren't selected to eliminate that trait at the breeder's, it will crop up. Many of us had a 'first rooster' who was a horrible beast, and we put up with it way too long!
In a 'normal' flock, with several generations of birds, there's experience, chicks are raised by broody hens, roosters manage cockerels as they grow, and predators take the young and unwary (natural, right?) so the group develops towards healthy social behaviors.
Enough for now!
Mary