In the RS guide it says that if you arrive on a long-distance train at one of the 3 stations in Brussels that your ticket includes taking the intercity train to any of the other 2.
My question is whether this works in reverse, too. We are taking the Thalys train on to Paris and are staying closer to the Brussels Central station. Similar to the arrival commute, can we board an intercity train to Midi with our Thalys tickets?