Regarding prana, in the same text it is described in the context of "Six Lamps" teaching as related to the second level of experience as in manifests from the basis, and identified with rigpa. Again, I will not pretend that I fully understand this level of teachings. I am sure there are people here who can comment on this.
From the practical, experiential point of view, I believe quotes from "White Sail" by Thinley Norbu Rinpoche may be relevant.
If we do not believe in what we cannot see, it does not mean that it does not exist. If someone if blind, he cannot see anything, but this does not mean that what he cannot see does not exist, since it can be seen by others.
If we do not recognise wisdom display, which is the causeless manifestation of the clear appearance of great emptiness, we create the reality of subject and object. Through the reality of subject and object, we create general and personal phenomena. When manifestations of phenomena are perceived in the same way at the same time and place by a group of sentient beings, their shared perception creates the habit of agreement, and this habit becomes the habit of general phenomena. When manifestations of phenomena are perceived differently by individual beings even though they are perceived at the same time and place, their individual perception becomes the habit of personal phenomena. When the creation of many different habits increases the variety of phenomena until personal phenomena are shared by different individuals, it again creates general phenomena.
I interpret this the following way. Our experience is conditioned by our habits from previous lives. If our accumulated habits are not conductive to witnessing siddhi or other unusual phenomena of this nature, then they likely won't be present in our experience. If you and I and many other people share this predisposition, it will become a feature of what we perceive as shared reality. So, it is quite possible that in our current state we are unable to experience such things as general phenomena, and whatever siddhi we or others experience will be limited to personal phenomena, until we change our habits of disbelief drastically and acquire merit. But to encourage this habit of ours is probably not helpful.
Because sublime beings are miraculous, their histories do not fit within nonspiritual reality and ordinary, intellectual reasoning. If some people cannot accept these histories because they seem inconsistent and illogical, then they cannot logically accept any of the wonderful histories of the thousand Buddhas, including Buddha Sakyamuni, as well as those of all ancient, sublime scholars, the mahasiddhas, and even one's own guru. The histories of sublime beings can never be confined within samsara's boundaries because enlightenment can never fit into ordinary mind and its ordinary calculations.
If we expect the qualities of sublime beings to correspond to the rules of our preconceptions of reality, then we can never transfigure our nihilist habits to the glory of victorious omniscience.
Whoever is wise about the true meaning of the nature of appearance,
That wise person is close to attaining siddhi.
Or, whoever has stable faith with a simple mind,
That person is close to attaining siddhi.
Whoever thinks and conceptualizes,
That person is far away from obtaining siddhi.