According to Chapter 48, what are some common practices that do not necessarily make someone a Sadguru?

Chapter 48 of the Sai Satcharitra clarifies that many common spiritual practices do not automatically qualify someone as a Sadguru. The text states that the wise do not consider those who merely study the Vedas, know the six Shastras, or explain Vedanta as Sadgurus. Furthermore, practices like controlling the breath (Pranayama), wearing heated marks (Taptamudra), or simply giving pleasing talks about Brahman are not defining characteristics. As explained in this chapter, these outward signs or scholarly abilities are insufficient to identify a true Sadguru.