Time was you could just about set your calendar by the Japanese automakers' model rollout programmes. Four years, more or less on the dot. Year one, after a Tokyo motor show debut, a new model; year three, new nose and tail, new dashboard; year one again, full redesign, at least of body and cabin. Engines often carried over and it was not unusual to see a new powerplant or two shoe-horned in, maybe in year two or four, carrying over to the next redesign. Simples.