My mate was telling me he was going up the M6 at night with hardly any other traffic at about 78mph in the left lane. Next minute he has someone right up his ricker, so close he couldn't see their headlights. He slows down a bit, no sign that they want to overtake. Starting to feel a little bit intimidated after a couple of miles, he pulled off at a junction to join the motorway again. As he peeled off he could see by the array of aerials on the back that it was an unmarked Plod Skoda Octavia. What's all that about then? Goading people into speeding per chance?