I find that for long distances, you're probably right, but for shorter distances, it definitely tries to route me down little tracks with grass growing down the

I find that for long distances, you're probably right, but for shorter distances, it definitely tries to route me down little tracks with grass growing down the middle and foliage scraping the sides of the car to cut the corner off a bend in a main road. I think the algorithm should probably weight more highly the time taken to reverse back to a passing point, and trying to turn right out of a tiny road into a busy main road behind a queue of ten other cars doing the same (which it fooled me into doing a while back). I agree with you that it doesn't seem to really know the difference between a less-major A road and a farm track. This makes navigating over Dartmoor interesting. And the roads are the wrong colours. </grumble>