The GMC isn't considered a 'serious' cabal. Instead of occupying an urban presence the GMC is a core of four mages who tour Greater Minnesota (i.e. not the metro area) keeping contact with mages unwilling or unable to relocate to Duluth, St. Cloud or the Cities. The four core mages tour in a van that they live out of, stopping in for a week or so to meet, greet and check up on mages and then moving on. The actual count of rural mages varies greatly as teenagers grow up and go to college, but there are at least three longterm rural Thrysus mages (near Branierd, Bemidji and International Falls) who show no signs of 'coming in out of the cold'.
The lack of interaction with mage society hurts the GMC's reputation. They enter the Cities perhaps once every two or three months, certainly not enough to maintain a political presence. They act as a stabilizing agent, keeping mages from ending up isolated or, worse yet, untrained in the hinterlands. However they do serve a large role in channeling talent towards the Cities and, incidentally, towards the Grey Lady. Mages to their credit include Smoke and Jazz of the Scottish Cabal, Euphoria of Block E, Demosthenes and Bacon of College and Sicilian of Frogtown.
The GMC is almost exclusively Free Council. Neither the Silver Ladder nor Adamantine Arrows are very comfortable with a group of potential renegades patrolling the depths of the Minnesota woodlands. This has led to a few conflicts. Until either the Ladder or Arrows step up however, it seems unlikely the GMC will care much.
More than almost any other cabal, the GMC is spiritually oriented. Their history has seen a preponderance of Thrysus. Unlike the bustling urban city cabals, the GMC finds themselves in places that haven't been domesticated yet. While the farmlands of the southern plains and Red River Valley are in hand, the northern Minnesota forests are still home to things that aren't particularly tame. More than anyone else, the GMC deals with things on their own; when the nearest reinforcements are three hours away, self-sufficiency is the best option.
Lastly, the GMC is suspected of running an occasional bit of smuggling to the Cities, mostly from the northern edge of Superior past Duluth. Everyone's heard a story about a van looking like the GMC van pulling up to a warehouse or garage and unloading a mysterious chest. While it remains unproven, it seems likely that the GMC is in fact shuttling various items to the Grey Lady, past the eyes of Seraphim in Duluth or Pan in St. Cloud.