Having started this thread I want to thank all who have responded to my comments - even those who fundamentally disagree with me. That's what forums are all about after all.
I would have to concede that it would be difficult to monitor instances of dangerous riding, although I don't necessarily accept that in order to be qualified to judge, one needs to have current experience of competing on a high-powered bike. I once gave evidence in a court case involving someone charged with dangerous car driving, and the magistrate was quite happy to accept it even though at the time I had never driven any vehicle in my life.
There surely must be many who marshal at road races who would be qualified to judge. But, yes you're quite right. The question of impartiality could be a problem - probably would be a problem.
I too have no wish to see road racing "refereed", as I wholeheartedly agree that in general those who race on roads have the utmost respect for each other, and that the problem of dangerous riding is normally not a big issue. However, maybe it is an issue at an event like the NW200 which attracts riders who don't normally race on the roads, and whose attitude as a result could be significantly different. Enough said. I'm not suggesting for one moment that such riders be refereed, but that, where necessary, a timely word in their ear about their behaviour from the race director / clerk of course would be infinitely preferable to having a serious accident.