Or just stick to the speed limits . This said the surroundings of Lucerne are known for their strict enforcement, but in the UK the same is the case regarding strictness and rightly so.

Going less than 25 km/h (plus tolerance) too fast on motorways costs you CHF 260, over this it becomes a criminal case which will be decided at a court's discretion. And yes, one can be stopped if not reporting / following up when entering / exiting the Schengen space.