Roosters can get very aggressive and even dangerous if they feel they "rule the roost". An old timer that has raised and exhibited chickens for 50+ years advised me to never let a rooster mate in your presence. Not letting them mate while you are around reinforces the fact that you are the Alpha bird. He said that its best that when you enter your coop the rooster should vacate immediately upon seeing you. He trains this behavior by booting the rooster with his foot. He doesn't kick them hard enough to hurt them, just enough to make them leave. Trying to work with your hens can be difficult if the rooster is there trying to protect them from you. If you ever get spurred you will wish that you "ruled the roost". Also, a spur injury to your person can lead to a serious infection since a chickens feet are filthy.