When a bird is so full of raging hormones, that he sees absolutely everything, and everyone as a threat to 'his' flock, it's not a healthy situation for anyone. The owner needs to be able to care for the flock, and should be able to do so without getting attacked. An animal that aggressive is acting out of terror and panic. Imagine having to live every moment of your life in complete terror of your flock disappearing. Imagine living a life so full of stress, being on constant alert for the next threat, to the point that even the person that brings the food and water is considered a danger. It's not a healthy way to live, and there isn't really a safe alternative. Caponizing is a very risky procedure. And I could not, in good conscience, pass a rooster like that on to someone else. It's just too much of a liability. And it's not fair to force those roosters to exist in such a state of mind. At least they can serve a purpose and be useful, by becoming a meal.