What does Chapter 10 say about Sai Baba's sleeping habits and the wooden plank?

Chapter 10 of the Shri Sai Satcharitra describes Sai Baba's extraordinary sleeping arrangement. He would rest on a narrow wooden plank, only about nine inches wide and four cubits long, that was suspended from the rafters with old rags, like a swing. The chapter notes that lamps would burn at his head and feet while he slept on this precarious plank. Most remarkably, his movements were completely imperceptible; no one ever witnessed him climbing onto or descending from the plank, a feat attributed to his great Siddhis, or divine powers, which made the plank's physical support almost irrelevant.