Yeah if you feel so inclined rflib, or routelib or something like that would help keep naming consistent.  But its not a blocker.

Another option would be to move it to sl/route.py or something more creative (sl/spray.py, after his boat?).  Then if when we end up using a method from rtefcst in other parts of the code we can push those routines into a library module.  Bug again for now I'm fine with the current name.