The ServiceJourney allows the user to set the JourneyPatternRef. This allows the end user to use ServiceJourneyPatternRef, ServicePatternRef, DeadRunJourneyPatternRef and JourneyPatternRef.
Shouldn't we limit this to ServiceJourneyPatternRef?
This would break some things, especially if we change the element name too. And would certainly break the Nordic profile. But I honestly can't see why this type would be so wide.