3 posts - and 3 rants! I see we have touched a nerve here!
I just had to get this off my chest and I'm glad it's not just me.
The slip road thing I see at least once a week down here. Its usually an older car with an old driver but I have seen other types of driver do this.
Having worked in an insurance office I've never seen a knock for knock where the driver in front braked for no apparent reason. The insurers take the line that the following driver should keep a proper lookout and maintain a suitable stopping distance. Its the same with speeding drivers - speed is not viewed as negligence as far as insurance claims go from what i've seen.