I hope I said roosters are a crap shoot, I almost always do say that. There is no proven way to always get a good rooster. People tend to think if I do this, he will be fine. That is not true. I agree with you, a lot of it is hereditary, but I think that there are roosters that do not take to confinement either, and if in a much larger flock, with a lot more space, much more than most backyards can accomplish, you can get by.