I want to contribute to the Sai community. What does the preface say about how writing or studying biographies serves the Guru and the public?

The preface in Chapter 0 details how writing and studying a Guru's biography is a profound form of service. For the writer, studying and performing Parayans of a detailed poetic Guru biography constitutes Guru service. Simultaneously, when other devotees study the work, the writer gains the merit of serving God in humanity (Jan-Janardan) and performing public service. The text emphasizes that the Sadguru takes service from devotees through books, either by writing great works themselves or, more relevantly here, by having their biographies written for the congregation to study, which in turn helps those devotees achieve the purpose of their lives.