How does the story of the doctor's nephew effectively demonstrate the supreme power of Sai Baba's Udi?

Chapter 34 uses the story of the doctor's nephew as a powerful illustration of Udi's glory by contrasting the complete failure of human expertise with the simple grace of Sai Baba. The chapter first establishes the problem as medically impossible, describing the bone-cyst as an 'extraordinary malady' that exhausted the efforts of numerous doctors and expert surgeons who tried every available native and foreign treatment, including surgery. This highlights the absolute limit of medical science in this case. Then, against this backdrop of failure, Sai Baba's solution is presented as remarkably simple: applying Udi. As Chapter 34 states, smearing Udi from Sai's hand could 'completely uproot the pain' of a terrible disease that no other remedy could touch, thus demonstrating its divine and miraculous healing power beyond human comprehension.