Are Swiss scenic trains worth planning around?
Scenic trains are worth it when the journey is the point. If you are using them only to connect famous places, slower routes, seat reservations and weather can turn the romance into expensive logistics.
Answer
Swiss scenic trains can be memorable, but they are not mandatory proof that you visited properly. The best reason to choose one is that you actually want a slow rail day: windows, valleys, high passes and the pleasure of not doing much else. The weaker reason is fear of missing a famous brand name. Some scenic routes add time, require reservations or pull the itinerary away from places you wanted to sleep. Others can be replaced by regular trains on similar corridors with more flexibility. Treat scenic rail as an experience to budget time for, not a decorative line drawn between mountain bases.
Recheck before you go
Transport schedules can change. Check current timings before you book around them.