I agree. The view of Endless and Eternal seem to be the minority view.
http://www.rinpoche.com/teachings/buddhanature.htm
Venerable Khenchen Thrangu Rinpoche
The Buddha Nature
The three phases of impurity, both purity and impurity,
And of complete purity are respectively:
(The phases) of beings, Bodhisattvas, and the Tathagatas.
Though this is what is said, Buddhahood is not newly created.
As it was before, it is the same after.
It is the changeless Buddha nature.
The “change” is becoming free of the stains.
If someone has the negative view
That the Buddha qualities have no cause,
Or conceive them not to be within oneself,
But created by external causes and conditions,
What difference is there between that and the eternalist and nihilist views of non-Buddhists?
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If one states that (wisdom) has attachment for its own appearances,
Then a mirror that has appearances within it
Would (also) have thoughts of attachment
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Wisdom is the three permanences:
Permanence of nature is the dharmakaya;
Permanence of continuity is the sambhogakaya;
Uninterruptedness is the nirmanakaya.
There are three impermanences:
Mentally fabricated emptiness is impermanent;
The mind of moving thoughts is impermanent;
The composite six consciousnesses are impermanent.
However, the three permanences are present.
The three impermanences are stains.
The three permanences are wisdom.
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Khenchen Thrangu Rinpoche, from 'On Buddha Essence: A Commentary on Rangjung Dorje's Treatise':
"The ordinary mind is just the natural or uncontrived state or the essence of mind. For that reason, the buddhas, bodhisattvas, and siddhas, those who are realized, are not in any way improving ordinary mind, buddha nature. The true nature of mind remains exactly as it is. Those who are in samsara or the lower realms are not in any way creating any deterioration of the true nature of mind. Buddha nature remains the same, but there are those who are able to relaize this true nature of mind and those who have not been able to realize it. Ordinary mind, or buddha nature, is permanent and it does not change. It is said to be permanent because it is the same whether it is realized or not.
Some scholars have attacked this position, saying that, in that case, this buddha nature is the same as the atman, or the eternal soul of the non-Buddhists. But it is not the same as the atman of non-Buddhists. If it were a permanent entity, those scholars would be correct. But Rangjung Dorje says that buddha nature is not a thing, that its nature is emptiness, that it lacks reality. Something that is empty, something that lacks reality, is permanent and will never change. There is no impermanence in the state of emptiness. Therefore the ordinary mind, the buddha nature, is a state of permanence which, at the same time, does not fall into the extreme of eternalism."
Elsewhere, he said, "The reason that we can't find mind when we look for it is that mind doesn't have an essential nature of its own. This nonexistence is what the Buddha calls emptiness, or shunyata. This emptiness does not need to be verified through complicated philosophical reasoning; it is simply the nature, or essence, of the mind."
"The word
emptiness, of course, connotes nothingness and makes us think of something like empty space, a mere absence, such as the absence of any qualities or content. But the emptiness of the mind is what is called “emptiness endowed with the best of all aspects.” This means that while the mind is empty, it is not a voidness; rather, it is cognitive lucidity. This means, for example, that when you look at your mind, you do not find the mind, nor do you see thoughts in terms of their having a location or possessing substantial characteristics. The mind and the thoughts within the mind are empty but they are not nothing, because there is an unceasing display of mind’s cognition. This shows that the absence of substantial existence does not mean that the mind is dead like a stone. For this reason, the realization of this absence of true existence does not cause the cessation of experience. "
Again as I said, the Buddha-Nature spoken in Vajrayana, Mahamudra and Dzogchen are utterly empty and unestablished, without core, Self, or substance. Buddha-nature is understood as the union or *inseparability of luminosity and emptiness*.
In fact Thrangu Rinpoche explains here in this audio - that ignorance is not because "luminosity is dulled" or one is "shrouded in darkness", but rather ignorance means the Luminosity/Cognizance/Awareness is so bright, so vivid, that it is taken to be substantial, to be real, and we fail to see its emptiness aspect. This is how samsara 'begins' (without a beginning, but it is one of the important conditions).
The audio:
http://www.rinpoche.com/q&a.htm
"If the nature of mind is this all-pervading, brilliant union of luminosity and emptiness, ungraspable, how is it that it could be obscured, even for a moment, let alone lifetime after lifetime?"
p.s. Some of Khenchen Thrangu Rinpoche books are great and recommended, i.e. Thusness and I recommends "Essentials of Mahamudra: Looking Directly at the Mind" but others are also well-written