My friend's chickens just got attacked by a pack of dogs (possible feral). The chickens who went to hide behind their rooster were protected. He said that he saw the dogs come around the truck, see the rooster, and double back immediately. Only the hens running around frantically were hurt.
I wouldn't bet my money on a rooster protecting the flock. In fact, 9 times out of ten, the rooster is going to end up dead by standing up to a canid, or most predators really. The rooster's job is to keep an eye out for predators and sound warning calls way before the hens do, which gives the flock enough time to take cover