I was reading this clarification today and came across the following which I thought may shed some light on the importance of making the progression from Bk to PBK.
Baba (Virendra Dev Dixit) says sit infront of the picture of the Trimurti at Amrit Vela and points of knowledge will emerge.
Unless you have taken the Gyan bath twice you cannot benefit. The one who takes the bath twice is called 'dooj' (twice born Brahmin)...The one who takes two births in Gyan. One birth is in basic knowledge where it was said I am atma, Paramatma is also atma, he is a bindu and I am also a bindu. This was the first birth.
The second birth is in the advance knowledge, that makes you twice born. That means you have taken two unlimited Gyan baths. You have to take these two births of Gyan. One birth is like taking a physical birth, when a child comes out of the womb that is called birth but he cannot be called a true Brahmin until he becomes 'yagyo pavit' (fully fledged mature Brahmin.) He has to imbibe the three threads (sutras) of Gyan in his life.
Only the ones who have understood the three sutras (three live forms of Trimurti) can imbibe. Yagyo pavit is the one who has fully understood the part of Brahma, Vishnu and Shankar. The one who has imbibed in his intellect who these three partdharis (actors) are, when they play their parts and in which form they get revealed, this means being yagyo pavit.
Until you have imbibed these three sutras (threads) of Gyan you cannot be called pukka Brahmin. So that is why there is no benefit until you have taken two baths (of Gyan)
This is an extraordinary experience to do this, the mind is totally engrossed in churning the knowledge, trying to work out how the pieces of the puzzle of the Drama fit together. The story of the beginning..the middle...and the end of the Confluence Age. It's all in the picture.
The mind is fully occupied and hence in a subtle stage, (Subtle Region in BK language) and ... it works!!