Don't understand the bikers reactions, just mob mentality. If I was the RR driver, calling the police would have been the last thing on my mind until I felt safe. All I would have been thinking about is getting out of there which is what the driver did. When they surround the vehicle at the next set of lights, my attitude would have changed and would no longer be in flight mode. It would be time for fight. It's at that point (the repeated second major intimidation) that I would have quite honestly been trying to run over as many of the bikers as I could because if I was the driver at that point I would be fearing for my life. It's natural human survival instincts, fight or flight, the RR driver tried flight to no avail.