"[T]here are some fundamental problems to be overcome. . .Robert L. Large Jr. began with the premise that our beloved Emperor is already dead, and he went on to describe the subsequent battle between the various heirs for the Petal Throne. In his version, the Emperor’s single Aridani daughter, Princess Ma’in Krythai won the battle and is now Empress. At last report, however, the Glorious Sixth-First Seal Emperor, Hirkane Tlakotani, is still alive and well in Avanthar, although a trifle slowed by his seventy years! We thus have an immediate and serious case of “parallel universe” development!
"A central headquarters and clearing house for Petal Throne information could be set up, of course, but this does not solve all of the problems. For example, two referees might grant the same fief to different players; one referee might initiate an Empire-wide rebellion; another might begin the Yan Koryani invasion; and still another might just allow the dreaded Black Ssu to run every human off the planet!" Reports Submitted to the Petal Throne, Dragon magazine #4
Kieth A Abbot tries to tackle the problem a different way, and he only needs 55 people to join in!
"I would like to tell you about the massive campaign that I have been working on. It is situated on the hypothetical world of Loera, a world of infinite possibility in fantastic adventure. Although it is not our own Earth, it is only about eleven light years from our world, and therefore most of the culture is a parallel of our ancient cultures.
"However, the scope and size of the campaign is so much that I cannot create and run it all. Therefore, I am putting it on a national basis so as to get the entire campaign running. I need fifty-five Dungeon Masters with time, and good judgment, who are willing to run an area about 600 by 600 miles. Each DM would gather up about twenty players, fill in any needed terrain and dungeons, and run that section, sending me monthly reports to keep the campaign up to date." Out on a Limb, Dragon Magazine #5
West Marches, Flailsnails, Starslugs, they are just the beginning. It is not in having the idea, it's in the doing.