Did Saruman Believe He Could Master The One Ring?

[Mithadan]

I agree that there is no doubt Saruman thought he could master the Ring. A related question is could he have mastered it and how fast? Clearly Sauron was not alarmed when he believed that Saruman had secured the Ring. Look at his response when Pippin is revealed in the Palantir:

Tell Saruman this dainty is notfor him. I will send for it at once.

And then, of all things, Sauron laughs! He was not truly alarmed! Sauron clearly believed that Saruman could not claim the Ring for himself and control it, at least not quickly. To recover it, he sent one Nazgul. Although Gandalf believed that Saruman and Orthanc might have the power to resist a Nazgul, Sauron seemed to think a Nazgul was enough to coerce Saruman with the Ring!

The answer here seems to rest in the fact that it would take time to learn to use the Ring. I am trying unsuccessfully to find the reference but am unable to. Somewhere, Gandalf states that after Frodo claimed the Ring in the Cracks of Doom, if it had not been destroyed the Nazgul would likely have feigned obeiscence to Frodo only to later seize the Ring or bring Frodo to Sauron. Frodo could not learn to control the Ring rapidly. Even Saruman would need some time to learn the use and secrets of the Ring. But what of the principle of the Ring giving its wearer power in proportion to the wearer's stature? If this is the case, Saruman's power with the Ring, particularly given his study of the matter, should have given him significant power. There seems to be a disconnect here. Shouldn't Sauron have been much more concerned?