[Talk-us] US highway classification

[Nathan Mills]

> You agree that if a router has two possible roads to take between two
> cities, and one is a trunk, and one is a primary, and all other 
> things
> are equal, that the router should choose the trunk, right?  Doesn't
> that make trunk, by definition, the primary non-motorway route 
> between
> two cities?

 Only if trunk has a meaning that implies that a road tagged trunk is 
 somehow better than a road tagged primary, which it apparently does not, 
 at least in some people's minds. If you're going to waste trunk on curvy 
 two lane roads, a router may as well use distance or maxspeed as a 
 better metric. As it stands, some of us are using trunk as more of a 'I 
 know it when I see it' thing than something useful for routing purposes 
 like motorway.