I’M ALWAYS AMUSED BY THE FREIGHT RAIL ADS that air on WTOP radio every morning. According to the ad, freight rail eases traffic congestion by taking 427 (or some such number) of trucks off the road for every freight train on the rails.

Well, yes, that may be true - but those are long-haul semi-trailer trucks that primarily ply the interstate highways. They don’t typically contribute to local congestion (with the possible exception of the outer loops around the city); it’s the thousands of box trucks that unload those freight trains and make local deliveries that do.