"There's nothing so practical as a good theory." Kurt Lewin (known as one of the modern pioneers of social, organizational, and applied psychology in the U.S.) is right, but his advice takes us only so far.
John Kania and Mark Kramer recently reflected on the state of the collective impact movement, in "Advancing the Practice of Collective Impact". The FSG team gets high marks in my book for being consistently open to adapting their theory to better reflect practice. Five years later, "collective impact" has permeated the waters in ways that FSG couldn't have anticipated or imagined. FSG has wisely opted to monitor but not try to control. But the water level is undeniably higher.
By any name used, those of us committed to sustained community change are now being held to higher standards and expected to demonstrate better skills. In some ways, the fact that FSG's initial theory had serious omissions (as noted by Tom Wolff in a recent critique, "Ten Places Where Collective Impact Gets It Wrong") actually helped galvanize consensus around the importance of not only acknowledging but accelerating community inclusion and a systemic focus on justice and equity. There's still much work to be done, but we are making progress.