I'd say Esworthy is closer to a neighborhood road than a primary road.  I tend to agree that the River/Esworthy/Seneca/28 route is one of the more significant routes in practice, but calling it "Primary" is way overstating its significance.  And I'm reluctant to say that the difference is enough to mark it as a different class.  Pushing so many roads into the upper tiers of the classification system removes helpful detail from the maps.  Why not classify everything as motorways and be done with it?