All of the 'routers' are using heuristics to select what they see as "best route". And one of the heuristics is likely "prefer main roads". If you run /any/ o

All of the 'routers' are using heuristics to select what they see as "best route". And one of the heuristics is likely "prefer main roads". If you run /any/ of them while driving an area you know well, you'll see many instances where the route the algorithm picks is not the route you would have chosen yourself (i.e., they don't know about the 'shortcuts'). Their benefit is when you are in an area where you do not know now to get "there" from "here", the algorithms will usually get you to your destination. Maybe not by the "best" method a local would have chosen, but they do get you there.