I agree with your assertion. The view of Dzogchen is in harmony with the vision of both schools, Madhyamakha and Yogacara. The essence of Buddha-nature, as explained by Mipham Rinpoche, is the union of emptiness and luminosity. In the teachings of the second turned, the Buddha taught the principle of sunyata, while in the third, the Buddha-nature: luminosity.asunthatneversets wrote: Of course there are certian Yogācāra tenets that Dzogchen implements in its system such as eight consciousness model, but when it comes down to the view in principle one can also say that Dzogpachenpo closely resembles the Madhyamaka view (not in praxis, but in principle).
The two quotes you posted above for Madhyamaka and Dzogchen are not all that different since the "ground" (or rather, 'basis') which is mentioned in the Dzogchen quote is original purity... a principle which is also referenced in the Madhyamaka quote: "...both in their true nature are originally pure."
The separation between emptiness and luminosity is what makes the tendencies of nihilism and eternalism arise.
My view is that Madhyamaka and Yogacara teachings are complementary, not contradictory, and the view of Dzogchen is their union. The teachings of Yogacara offer a better explanation of how the unenlightened mind can be transformed into enlightened mind:
"Enlightenment consists in bringing the eight consciousnesses to an end,replacing them with enlightened cognitive abilities (jñāna). Overturning the Basis turns the five sense consciousnesses into immediate cognitions that accomplish what needs to be done (kṛtyānuṣṭhāna-jñāna). The sixth consciousness becomes immediate cognitive mastery (pratyavekṣaṇa-jñāna), in which the general and particular characteristics of things are discerned just as they are. This discernment is considered nonconceptual (nirvikalpa-jñāna). Manas becomes the immediate cognition of equality (samatā-jñāna), equalizing self and other. When the Warehouse Consciousness finally ceases it is replaced by the Great Mirror Cognition (Mahādarśa-jñāna) that sees and reflects things just as they are, impartially, without exclusion, prejudice, anticipation, attachment, or distortion." http://www.acmuller.net/yogacara/articles/intro.html
Two books that I recommend about the subject:
Rangtong & Shentong Views http://amzn.com/B00506TUWS and Luminous Heart http://amzn.com/B0028ADJKS