Mercer is going to have to test the wind carefully. The relationship between CR and D&D is a weird circular one. Years ago, CR brought people to D&D. But more recently I bet D&D brought people to CR. And as I understand it, CR fans skew older than most new D&D fans - 30-ish rather than late teens. I don't recall where I read that, though, so I won't plant a flag on it. In either case, knowing what percentage of his fans will follow him anywhere will be really important if he chooses to drop D&D for idealistic reasons.