Why does Chapter 11 emphasize the necessity of a physical Guru for a devotee's spiritual practice?

Chapter 11 emphasizes the need for a physical Guru by stating that as long as the worshipper has a form (a body), the Guru must also be in a physical form to facilitate devotion. A manifest Guru provides a tangible focus for worship; one can place their head at his feet, exchange words of love, and make offerings. The chapter argues that without meditating on this Saguna, or manifest form, true loving devotion cannot easily arise. It is this tangible connection and the love it fosters that serves as the foundation for the devotee to eventually grasp the more difficult concept of the formless, or Nirguna.