According to Chapter 48 of the Sai Satcharitra, what are some characteristics that do NOT define a true Sadguru?

Chapter 48 of the Sai Satcharitra clarifies that many common spiritual achievements do not, by themselves, qualify someone as a Sadguru. The wise do not consider individuals who merely study the Vedas, know the six Shastras, or explain Vedanta to be Sadgurus. Furthermore, practices such as controlling the breath (Pranayama), wearing heated marks (Taptamudra), or giving pleasing talks about Brahman are not the defining signs. The chapter also notes that simply giving mantras from scriptures is insufficient, as this knowledge can be 'verbally hollow' without the Guru's own direct experience.