Aggression in roosters is genetic. A rooster can turn aggressive no matter how they were handled or raised, at the other end of spectrum there are roosters that will never attack, even if taunted as long as the days are.
A lot of roosters fall somewhere in between. The recent example could be a good one- a rooster that might not attack under "normal" environment but goaded into it by being taunted. It's not different from encouraging and "training" really. For most of the "in the middle" or less aggressive roosters, ANY method of discouragement applied immediately and swiftly in a case of attack can be enough to deter the rooster from charging again. Or he may do it a second time and if "discouraged" may never do it again.. It doesn't have to be picked up or cuddled, which can work BUT in reality, anything swift and immediate like a kick, grabbing by tail and "swinging" it away will give it a rude surprise because their instincts are not programmed to expect that. They won't like it.. and if they are low on the aggression spectrum this will be enough.
The problem or "failures" tend to be on high middle or high on the aggression spectrum, they will attack again, irregardless of how they are handled. Some "bad cases" that could have been deterred early on were only encouraged by teasing, thinking it's funny(at first..) or reacting improperly which only encouraged the aggressive insticts such as shrieking and running away- that's POWERFUL reinforcement to a charging rooster as that is what he expects by instinct. This is why there can be a lot of conflicting responses.. it is the assumption that all roosters are the "same" but they're not.
Lastly, a wonderful example of rooster aggression being genetic can be found in fighting game rooster lines. There are lines selectively BRED to be handleable, which means not charging, attacking or "fighting" people.. kids could pick up and handle those chickens with no fear.. however they have not lost one bit of their murderous desire to kill any rooster within reach. Actually, lines with roosters that attack anything including people have a specific name for them- "man fighters".
As the rooster this thread was started over was a RIR, aggressive roosters are a rather common side effect of lines being selected and bred exclusively for production qualities with no culling for any other trait. So if genetic aggression happens to be in the founding stock, it can happen that aggression is unintentionally bred along the high production with the result of a backyarder finding out their production cockerel starts attacking them. Another possibility is that some feature of high production has a link to aggression so it cannot be culled out of that line without losing production.
Super-lastly.. you don't need a rooster, unless you intended to hatch eggs.. there's always other roosters also..
If you are not going to let them mate then you should get rid of the rooster. You may think he's just "being naughty" but he is trying to fulfill a biological need that he was born with. It is not dirty, it is not filthy and it is not mean. To put the hens in front of him and then push him off when he mates is simply cruel. It is no different then him eating or drinking. These animals have needs and instincts that they need to fulfill and it is not just to be cute fluffly playthings for ourselves.
