What is the relationship between different forms of biographical writing and achieving the ultimate spiritual goal?

The preface in Chapter 0 outlines a hierarchy of writing as a spiritual service. It states that writing biographies of worldly figures is a worldly service that does not yield spiritual fruits. Moving up, writing about many saints is a form of Guru service that can provide some spiritual benefits but is considered partial and ultimately insufficient for reaching the final goal. The text asserts that the most certain path to attaining the ultimate spiritual goal of salvation through writing is to compose the biography of one's own Sadguru and engage in its regular, devoted study and recitation.