A VERouteOptimize Enumeration value specifying how the route is calculated.
The default value for this property is MinimizeTime. This means that the route will be calculated to minimize the route time.
You can set the VERouteOptions.UseTraffic Property to true if you'd like the route to consider available traffic information to minimize the route time.
If the RouteOptimize property is set to VERouteOptimize.MinimizeTime and the VERouteOptions.RouteMode Property is set to VERouteMode.Walking, then an empty VERoute object is returned.