Here's what I saw after watching that entire video. And if the victim (I say that because he was wronged, by you) takes it to court and enters it as evidence you will get your as$ handed to you, as it should be.
First, he was in complete and total control. Only at WOT for short bursts, anybody with half a brain can hear that.
Second, he did not have any near misses. Maybe the conditions weren't ideal for an average rider. You can cite that. He and his buddy obviously had the skills to ride at that level.
Third, I saw several other S.P.O.Rs ( Stupid People On Rentals) parked in the trail, not wearing proper safety gear and putting themselves in harms way.
Fourth, How fast and out of control were you operating your sled in order to catch up? Obviously much faster than they were going because you caught them. Which brings up another point, if you caught them that fast means they OBVIOUSLY were not at full throttle but you were. No Trail Cop 600 will catch an 800 if both are at WOT. You should know that, given all of the miles you put on a year.
Fifth, after pulling them over (they parked on the side of the trail, out of danger) you left your sled in the MIDDLE of the trail, in the line of fire and thus, putting them in the line of fire with you.
Sixth, instead of just being a professional and issuing a written warning, you cite them? Did they have prior offenses on the trail system that we are unaware of? If not, 9 out of 10 cops would have issued a verbal, just asking the riders to slow down. In my book, that makes you the cop that everybody b*tches about.
I imagine (one would hope anyways) that you watched the video. And now you feel like a complete toolbag. They were in control, they pulled over as soon as you signaled them to, they were polite and cooperative. Did you clock them at an exact speed and note how fast they were going over the speed limit on the trail, if any? No, you used your own personal judgement and if I took that GoPro footage to court I could beat that citation 6 ways from Sunday.
That's how I see it. And my wife is a cop, as are a good handful of my friends.