This seems to be a very rum deal and pretty wonky to me.
All I know is that Traffic police vehicles including my ex police ST1300 when it was in service, have to have their speedometers correct and calibrated , usually at six monthly intervals.
I have never heard of or been witness to someone being booked for speeding without the officer being able to reliably prove and substantiate what speed the offending vehicle was doing.
As far as I am concerned for a LEO. to say that he estimated either my or someone elses speed to be X and to expect me to accept his (obviously biased) opinion and then cop it sweet together with the appropriate financial and demerit point penalty to be applied for exceeding the mandatory speed limit.
That will never happen!!!!
I sincerely believe that the burden of proof for any alledged offence , in this case , speeding, lies with the official party having to prove their presented details, (opinions). To the total satisfaction of the Judge.
In my understanding of the law, a so called estimation does not fill this criteria.
That is my 20 cents worth.
If they can not, or do not, do this, then the procedure should be thrown out of court.
Cheers, Winston66