That's a massively faulty assumption that many people unfortunately make. The only way to say it's "not a map problem" is to have edited every junction along the route and adjacent to it, and to have correctly Typed the segments. Simply checking to see if there's green arrows along the route is not enough as there's currently no visual way of distinguishing between soft and hard allowed/restricted turns without QW'ing each junction.rogerl50 wrote:And it's not a map problem, because I can get it to give me that route by changing the starting point.
That you're getting different results based on starting point*, is a big indicator that the junctions involved have not been fully edited and that there's still soft allows/restricted. Soft allowed/restricted turns cause all sorts of odd routing due their apparently low penalties. And yes that means soft-allow has a penalty vs hard-allowed, or at least that's what testing seems to show.
*caveat: really long routes > 200miles are still unstable, especially if there's data coverage gaps, see this post.