Now I'm mapped it was hard to use it with the rain today.
So much standing water and the journey was half motorway and half A road and country roads.
I only managed 38mpg over 100 miles but I suspect that's because I enjoyed the twisties and used as much power as I could.
I do think that the standing water on the M40 wouldn't have helped much even though I only sat at 73 mph most of the way.
Any thoughts on the water and resistance...?