FILE IT, FLY IT!
Sorry but this is my point of view. Capacity in some sectors is close to 50 acft/hr and often the flight demand is above 70 per hour during peak hours. Even under regulation happened that we experienced in overdelivery problems due to wrong assignment of the requested/filed cruising flight level.
Have a look on:
EUROCONTROL - Flight Plan & ATFCM adherence
http://www.eurocontrol.int/dmean/gal...hure_Apr09.pdf