Wikipedia says that several companies run freight trains over sections of the NEC, as well as the line is also used by commuter trains.
https://en.wikipedia.org/wiki/Northeast_Corridor
As a comparison, the TGV connection between Paris and Brussels may be a high-speed track, but train speeds grind to a halt way down to 20km/h when passing through track sections used by commuter and freight trains.
Wikipedia says that several companies run freight trains over sections of the NEC, as well as the line is also used by commuter trains.
https://en.wikipedia.org/wiki/Northeast_Corridor
As a comparison, the TGV connection between Paris and Brussels may be a high-speed track, but train speeds grind to a halt way down to 20km/h when passing through track sections used by commuter and freight trains.