According to Chapter 11, why is it important for a devotee who has a physical body to worship a Guru in a manifest, or 'Saguna', form?

Chapter 11 of the Sai Satcharitra explains that for a worshipper who has a physical form, the Guru must also be in a physical form. The text states that this is the determination of the scriptures. It argues that devotion does not truly manifest without meditating on a Saguna, or manifest, form. As long as loving devotion doesn't occur, the 'bud of the mind' does not open and bloom, meaning it cannot produce the fragrance and nectar that attract the divine, much like a bee to a flower. Therefore, meditating on the manifest form is presented as a necessary step for spiritual development.