Originally Posted by sean
However, to prevent people using the long distance trains as a "rat run" between Manhattan and Fordham, where their own local services or the Subway would be more appropriate, the stops carry restrictions, marked in the timetable as "Stops to Recieve passengers only" for trains leaving Grand Central, or "Stops to discharge passengers only" for trains going in.
Here in England there are several examples of such restrictions, particularly at major stations just outside London, such as Watford Junction, where many long distance trains which make this stop, including trains serving Holyhead for the Irish Ferries and sleeper trains to/from Scotland permit boarding only outward from London and Alighting Only on inbound journeys from London.
The idea of Dublin-Belfast trains perhaps at a future date stopping at Howth Junction would make sense if there was eventually a DART link from Howth Junction to Dublin Airport (Much more useful and cheaper to build than the much-delayed Metro line). Potentially, Intercity trains could even travel via Dublin Airport as well if such a route was built.