Yes — this is well-established in interior design. Light-colored curtains at the windows visually expand a room by creating a sense that the walls extend to the window and beyond. Snow Chinook, in particular, being a pure, bright white, maximises this effect. For maximum visual expansion, hang the rod higher than the window frame (close to the ceiling if possible) and extend the rod width beyond the window opening — this creates the appearance of a much larger window and a taller, more open room.