Fig. 1 M25 traffic - on a good day
This was for a 135 mile journey, mostly M23, M25 and M40. I've done worse : 27 mph the same journey. Sometimes you wonder whether to take the car out or not. Crawling around the M25 has become my recurring nightmare : you've got to plan for lengthy delays with a tank of fuel, water and grub. At least I had our teenage son with me so I got to hear and ask about a substantial part of his iTunes playlist. And an automatic - a few years of stop starting in jams made me a convert. I'll have a self-driving car please then climb in the back to sleep, read, watch a movie or go online.