Then why have we not had a correspondingly "significant number" of incidents?

There are also a significant number of motorists who are threat but not all of them cause accidents, Jim. A threat is just a threat. Only a small proportion of threats turn into incidents. Thanks for, seemingly, accepting that I have indeed given an opinion. Why it has taken so long is beyond me and it still does not answer my points to you but I wait in hope.

Cheers

DtG