Mark --
Another theoretical way to analyze overall success in soccer in South Carolina is to assume that clubs and coaching have little to do with state cup victories, but rather raw demographics drive the overall picture. By this I suggest that it is not unreasonable to assume that an area of 500k population should produce twice as many State Cup championships as an area inhabited by only 250k people.
For testing purposes I decided to use Greenville, Richland and Charleston counties as the center points of analysis and take the three most populous contiguous counties as the "surrounding area". (US census data
http://quickfacts.census.gov/qfd/states/45/45045.html) This may not be a perfect model but serves as a reasonable starting point for discussion.
Rounded to a reasonable Saturday night level of math this yields the following:
Greenville, Spartanburg, Anderson, Pickens = 925k
Richland, Lexington, Sumter, Newberry = 684k
Charleston, Berkeley, Dorchester, Georgetown = 612k
With this in mind we would expect the Greenville metropolitan area to produce around 1.5x as many State Cup victories as the Charleston area given exactly equal club organizational skills (and roughly the same differential for metro Columbia).
I recognize that GFC and SGU outperformed this model, but would suggest only that they are aided not only by a solid club organizational structure but also by the fact that the upstate has a lot more kids to draw upon to form their upper echelon teams. Add to this the recruitment phenomenon for club play and the pendulum swings even further in the Piedmont's favor.
Food for thought.
lpaf