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Conclusion and Commentary
The SCC is often required to make decisions which are not popular with it’s users (airlines and other ATC facilities). The airlines prefer of course to keep to their schedules as much as possible, while controllers find their job easier when delay programs are implemented. Cultural differences exist between airline operators -- some prefer to fly and hold, while others are more open to ground delays. The current low price of fuel is believed to make ground delays less popular. Controllers flow program requests are often denied because the SCC data does not support a delay solution.
In general however, many of the problems handled by the SCC would not be visible at a lower level, nor could efficient solutions be devised.

Scenario: Fort Worth ARTCC
The Fort Worth ARTCC controls high altitude traffic over most of northern Texas. Within this airspace are numerous TRACONs, but the DFW TRACON is the dominant facility. TRACON airspace shape is typically described as resembling an upside-down wedding cake, with the airspace in the center extending down to the ground, but starting at higher levels moving out from the center. The DFW TRACON fits this general description, with the widest (highest) layer forming roughly a circle with a diameter of about 54 nm , geographically centered on DFW airport and extending up to 10,000 feet. While DFW is the primary airport served by the TRACON, Dallas Love Field, and several smaller airports are also within it’s airspace. Generally, arrival and departure routes are strictly defined to manage the flow of traffic.
Airways and ATC procedures direct DFW arrivals to four ‘corner post’ arrival gates arranged in a square about 25 nm outside of TRACON airspace, prior to entering the TRACON. Fort Worth ARTCC controllers issue speed and vector instructions to arrival aircraft to regulate flow through these gates to meet the arrival rate limit set by the TRACON. The TRACON arrival rate limit is normally a function of the airport limit set by DFW Tower, but sometimes the airport arrival rate is not the limiting factor (weather in the TRACON airspace, for example). On a VFR day with all runways available, DFW can land about 102 airplanes per hour. On most days, a single fix at each arrival gate is used to channel inbound traffic. However, each corner is actually configurable to support two arrival streams if necessary (two fixes) when allowed by the TRACON. In practice, only one corner is used in this configuration at any given time.
A typical jet arriving to DFW would be controlled as follows:
1.  
an abutting ARTCC would hand off the aircraft to Fort Worth ARTCC at cruise altitude and airspeed.

2.  
Fort Worth ARTCC would begin to sequence the arrival with others to the filed arrival gate, using speed control and vectors to provide spacing as needed to support the TRACON arrival rate.

3.  
At some point the controller would issue a descent, which may or may not be
　
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