How does the act of writing and reading a Guru's biography, like the Shri Sai Satcharita, contribute to the community and serve the Guru?

According to Chapter 0, a Sadguru accepts service from devotees through books in two primary ways: either by writing great works themselves or by having their biographies written by devotees. When a devotee writes a detailed biography, they perform Guru service. Furthermore, when other devotees study and perform Parayans of that work, the writer gains the merit of serving God in humanity (Jan-Janardan). This collective study, as with the Shri Sai Satcharita, allows the congregation of devotees to achieve their life's purpose and strengthens the bonds within the spiritual community.