Wayne, Good Luck in traffic court. You could plead good drivers record and in several states this ticket can and will be filed. It usually is a first ticket kind of situation.
The radar cannot tell the police officer anything, it merely recorded the speed of a vehicle in the cone of the radar, which is rather large and CANNOT pinpoint an individual vehicle with any certainty like a laser can. Its up to him to decipher the situation which you can bring up some doubt. The rear view mirror vision is a good point. Unless the officer has a bad track record with the judge, he will usually trump the rebuttal from the accused without a lawyer.
With a real charming and sound argument, and an officer with some doubt about what he determined ( and smile and say hi to him if you see him in court)
, may agree with you.
Lou