RC,

Rolling hubs are supposed to be more efficient for aircraft and crew. The aircraft at DFW (for example) continue to leave every 55 minutes all day long. The crews will leave immediately on the same or other aircraft.

On the other hand, the passenger may experience a longer connection due to the "smoothing out" of the banks of flights.

By the way, another term for rolling hubs is continuous hubbing (if that helps anyone).