Not wanting to get totally embroiled in a subject that really, really riles me, and not ignoring the "no real proof" elemnt of Pete's saga, but there is also the issue of:
Catching up.......
I remember seeing the paragraph in the ACPO guidelines on the operation of "Time & Distance Recording" equipment that elluded to "doing 100mph to catch up with said target vehicle does not in itself constitute that said target vehicle is doing 100mph so you have to track it at a constant distance for a predetermined distance to confirm it's speed on your
calibrated TDR equipment"
There's a very helpful site called
Pepipoo that we should all read and memorise the content of. It may not stop you getting nicked when you do 100mph but it may stop you getting nicked if Mr Traffic Officer hasn't done his/her job properly/within the law/guidelines as you'll be better versed to question (politely) every thing he/she states about how he/she came to their assertion about your speed.
I am of the opinion that if more people were educated better about their rights and the rules the officers should abide too, it would get rid of a whole raft of the "bent-brigade" who flout the rules and sadly do exist amongst the other finer examples out there.
I hold my hands up if I'm done fair and square, but if I'm not 100% certain I want to be damn sure they're 100% certain..............