[doug*platypus]

Going back to the original question (seems like half of my posts start out with this line!), I don't think that Saruman's ring would have any say in that particular matter. Saruman's staff, and his position in the "Order" (presumably the Istari) were based on a mandate given to him by Manwe and the Valar. In the brief time when Gandalf has left his body, and strays far on strange paths, it is my opinion that Manwe and the Valar give him new authority. They send him back as the White, with the power to expel Saruman from the Order on their behalf, if he continues to rebel against their will. Whatever power Saruman's ring does have, surely it can't stop the Valar taking back the power they originally gave to Saruman.

I would also have to doubt that Saruman's ring could come close to the powers of the twenty Great Rings. I don't think time periods are specified, but it is made obvious that the Gwaith-i-Mirdain were forging 'magic' rings for many years before Celebrimbor perfected the art. And all except for the Three and the One were collaborations, made with the skill, knowledge and expertise of more than one person. I don't think that even a Maia of Aule could learn much more from studying books than a crude knowledge of the craft.