What is meant by 'one-pointed devotion' and how does the story of Damu Anna serve as an example of its benefits?

As explained in Chapter 25, 'one-pointed devotion' is defined by quoting Krishna's words to Uddhava: "The Sadguru is indeed My own form," and that one should worship such a Sadguru with love. The text establishes that Sai Baba is the supreme embodiment of mercy and desires this kind of singular focus from his followers. The benefit of this devotion is that a faithful devotee will lack nothing and Sai will ward off all their misfortunes. The story of Damu Anna is explicitly introduced in Chapter 25 as a report to show this principle in action. It serves as an example of how, once one-pointed faith is established, Sai grants desired objects, like blessing the childless Damu Anna with sons, and removes suffering.