Well according to paragraph 21, page 178-180 of the "Jeremiah book" which was studied this week at the CBS it isn't vital at all:
A significant aspect of the new covenant is this: "I will put my law within them, and in their heart I shall write it. And I will become their God, . . . And they will no more teach each one his companion and each one his brother, saying, 'Know Jehovah!' for they will all of them know me." (Jer. 31:33, 34) The anointed on earth today have shown that they have God's law within them. They love the truths found in it, rather than relying on the teachings of any human. And they have happily shared Bible knowledge with those forming the great crowd. Thus, these with an earthly hope have also come to know and love Jehovah. They willingly submit to his direction and trust in his promises. You probably fit that description. You know him as a Person and have a personal relationship with him. What a benefit that is!
Is it just me, or were you also expecting to see 1 John 2:27 quoted or at least cited in that paragraph:
"And as for YOU, the anointing that YOU received from him remains in YOU, and YOU do not need anyone to be teaching YOU; but, as the anointing from him is teaching YOU about all things, and is true and is no lie, and just as it has taught YOU, remain in union with him."
According to the above quoted scripture and "Jeremiah book" excerpt, anointed christians are in no need of a faithful and discreet slave on whom they must depend to be taught about Jehovah, because they all know Jehovah through the operation of holy spirit within them. And please note that the expression to "know Jehovah" as used in this context is not limited to knowing the personality of Jehovah and having a personal relationship with him. It extends to living righteously in harmony with Jehovah's righteous standards. So 1 John 2:26,27 and the WBTS' own literature exposes them for the unscriptural, high-controlling, self-appointed masters of the faiths of all JWs, that they are!