I am not certain what the special items which would warrant fitting in second factory. But one can only assume it would be the select clubsport items not available or on the regular GTI. For example would it be the Bucket Seats, Centre Console modification, lack of ambient lights in the door cards, Exhaust, unique upholstery seating for clubsport, etc,. It could be any number of the kit unique to the clubsport which could otherwise slow down the production line of regular/performance golfs.