And believe me, it takes a lot of preparation. Objectives, orders, planning, the FSO is successfull because of all the work and planning that goes into it. I would guestimate that at least 30 man-hours a week go into planning each frame of an FSO, and god know how many hours are spent planning each month's entire event. Even at the squad level, there are hours of preparations to be made as well as practice. Trust me, holding FSO's more than 3 days a month would cause the FSO as a whole considerable harm.
This is why the FSO is so successfull. What are we everaging now, 500+ per frame?