I don't think Home Zone will take the headache of deciding the stops in other zones. If a train from JAT - CAPE need to be introduced then the home zone will die deciding the TT. A guy sitting in CSTM will feel difficult to understand the congestion in MAS to introduce a train. If home zone decides the entire route then they would prefer a fastest train connection. First it starts with originating(home zone will decide) and destination station(destination zone decides) slots. Then the intermediate stations TT will be fixed by respective zones. The home zone knows only the "Time entering in to that particular zone and Time out in that particular zone".