(total) cost vs average cost factor

[Jacques Fournier]

Hi,

I'm new to brouter, and what I understand is that best itinerary is the one with lower "cost".

And I understand that (total) cost = average cost factor * distance.

But it seems that brouter look for best average cost factor and not total cost. Why ?

Is there a way to have an itinerary with the best cost?

I understand that itinerary with best average cost factor can be more "pleasant", but less (total) cost better correspond to my demand, no?

See below, itinerary I modify manually to obtain a better cost.