I had heard of a series (Hillingdon?) where a 4th only race was run but no points awarded, and apparently the number of "offs" were much reduced. Do most crashes happen in the last lap or two when people get desperate to get a point and so take silly risks for a lower placing, instead of just easing back a bit and letting those in the first few get on with sorting out a winner? There must be a cause, and it's not hard to conclude that the number of poibts on offer for the lower positions is at least contributing to the problem. In days of old when I first started, it was twice in the first three or four times in the first six to get promoted up a category, which meant lower than that was only about any prizes offered further down.
Maybe the promotion needs to be separated from the ranking system somehow?
Now I'm off into the rain to get my legs moving - must be potty!
I haven't heard about it, but would expect fewer entries, and a different mix of racers entering. Most 4th cats are chasing points - sad but true.
I am seeing crashes at all stages of the race - I think the main cause is that it takes a fair bit of racing to get the right habits, and be able to maintain concentration for the duration of the race. I suspect the main cause is lapse in concentration, combined with not having the right racing habits ingrained. An analogy would be the difference in insurance premiums for newly qualified drivers versus over 40s.
Having said that, I also think that talk of crashes at 4ths races is somewhat exaggerated. I have seen 3 or 4 in the last two seasons, and was involved in 1.