cloudy said:well in that vein two photos taken with you in different positions on the road doesn't technically prove anything either - it's only in the fact that the timing has been deemed to be correct, that it becomes evidence.
Two photos are taken so that a human can analyse the photos, count the number of white dashes marked on the road between the first and second photo, and use that as conclusive evidence as to the speed you were travelling. Radar alone is not sufficient, as it is subject to bouncing off other vehicles, but provides a sufficiently accurate mechanism to determine if a photo pair needs to be taken or not.
I hypothersise that the reason the TVR didn't set the flash off at all because:
(a) The software working the radar is calibrated to assume a reading over a certain amount, like 170mph, has to be a false positive and assume its a reflection, not triggering the camera.
(b) The radar beam is actually emitted as a pulse at regular time intervals rather than one long continual signal, and that the car was travelling so fast it actually managed to squeeze inbetween a pulse.
(c) The car is too plasticy to actually reflect a radar beam
(d) Its Top Gear and they needed to have a happy ending to their story. They do like fabricated.. er I mean convenient endings to their articles.