I never said in my post the van was "justified" in hitting the bike, (if in fact contact was made). It "appears" he has edited out any contact, at first I thought it was a "jerk" of the camera during contact, but when I slowed the video, as the video restarts he is in the middle of saying something, so there is no "jerk" but rather it is poor editing.
No your are 100% correct you can't hit a vehicle in front of you because they are driving too slow for your liking. However, at the end of the video when he is telling his side of the story he says, I turned around and told him to back off. "Then he gave me the finger so I SLOWED DOWN". Now he doesn't say how he "slowed down" and that part "appears" to be edited out of the video. If he "brake checked the van" then he committed an offence. ANY novice rider should know that brake checking or even slowing down in front of vehicle you feel is too close is not proper nor smart riding. If he felt the vehicle was so close as to present a danger then he should have either accelerated away or moved over and let the vehicle pass, and thereby remove the danger.
The van didn't "run over" the rider. If you look clearly, as the van approached the rider actually, again attempted to block his advancement, then tried to jump on the hood. Unfortunately the caravan has no hood to speak of, and the rider fell off to the side as the van. The rider had an option to move to his right and avoid the van. A citizen has no power to attempt to stop or block a vehicle on a roadway. Many members here criticize an officer for stepping in front of a car, on a road at a radar check, (even though they have the leag authority to do so.
The rider had stopped in the first instance and was VERY aggressive in his actions when he apporached the van. If we are looking at this purely from an insurance perspective, then yes the van will be assessed fault. As for charges the van driver still has a valid defence of fearng for his safety, (based upon the riders aggressive manner in the first encouter and then his continuing aggresive manner of trying to use his vehicle to block in the van. All the van driver has to do at trial is get a reaonable doubt, (one juror is all it takes for his lawyer to convince).
Recall the guy in the suv in New York he wasn't charged as he said he feared for his life when he initially took off, due to the aggressive actions of the riders. Eventually this was bourne out when they dragged him from his vehicle, and beat him severely. Personally I wouldn't have waited to see what the rider was going to do next, (given his previous aggresive actions).
The rider SHOULD have, (after the initial contact), was gotten the plate number of the van, then mve his bike off the road, (he already had the driver face on video), and call the police. by pursuing the van at high speed he strengthened the van drivers cas ethat he was in fear as ths guy had yelled and acted aggressive towards him, so he tried to remove himself from the situation and the rider chased him down and tried to block him in.