An addition that's a week old, but I just came across it this morning. My 2nd letter to Coster...
Dear Police Commissioner Coster
I've seen the footage you were shown below from another angle as well. In that, it can be clearly seen that the gentleman in the red cap was stepping forward to help a woman who on the ground being pummeled by two police officers. And yes, it shows that he collapsed to the ground unconscious. That is, unless conscious people are in the habit of falling flat on their faces without trying to protect themselves.
I agree with you that "remarkable courage was shown" but in this situation it was shown by the unarmed, unarmoured man in his 70s, not by the police officers who punched him in the face.
RE: Policing and keeping the peace