John Reynolds (aka Vajranatha) exposed me to Dzogchen thru this book. He associated himself with Namkai Norbu (who wrote the foreword) and had the assistance for this translation on others who know Dzogchen, including Lama Tharchin who I had the great fortune to hear speak once.
If Dzogchen can be applied successfully, then it must be through reading books like this one that one "reaches" that understanding.
When I was new to Dzogchen, Vayranathra's commentary was helpful. It remains so, but to a lesser degree today, but that may be due to overfamiliarity with it on my part. The appendix, which discusses how Evan-Wentz and Jung viewed Dzogchen, was never very helpful to me and I am not clear that it would benefit anyone but scholars. My assumption is to ignore Evan-Wentz translation and go with Vayrarathra's, since it was the first I encountered, it was supported by some Dzogchen teachers, and it excited me about Dzogchen.
Since that time, having read "You aee the Eyes of the World" from Longchenpa, Self-Liberation is no longer my "favorite" Dzogchen text but it continues to seem to be one of the three most important I know of, these two and the other one being the Bon text "Heart Drops of the Dharmakaya". I confess that my practical understanding of these texts remains small after about 10 years of studying Dzogchen on and off, but it does seem to me to remain one of the more important possible ways of facing the world constructively.
Vajranathana has continued his studies of Dzogchen (both in Tibetan Buddhism and Bon) and remained closely associated with
Namkai Norbu. My impression is that he is one of the most, if not the most, reputable scholar/translator of Dzogchen. His other translations include "The Golden Letters" and "The Cycle of Day and Night". I'd suggest reading "You are the eyes of the world" postponing the introduction and commentary but rather reading first the main text of "Self-liberation through seeing with naked awareness", also postponing its commentary and seeing what effect they have on you. If they make sense, you may be on your way to being benefited by Dzogchen in a way you could never have anticipated either yourself or by what modern day writers try to tell you. My bias is to trust the modern translators and ancient text writers for the time being and see where that leads me, because the translators may be constrained by the ancient texts and the ancient text writers may be had less to gain in worldly ways then some modern teachers.
Well, that's just my two cents on how I have approached Dzogchen. It isn't certain to me yet that anyone at any time has really applied these teachings constructively: it may be a well-meaning comfort system and it may be a long-lived deception. That it means something to indicate I am conscious in a way that seems incredibly creative, without boundaries, and with staggering presence I won't argue with, but that may be natural aspects of what we find as our consciousness and being in the world, it doesn't mean that anyone is a master of it or that it is some great perfection that already exists but for which I should pay people to confirm. Be wary and enjoy this creative ride and be glad, as "Self-Liberation through seeing with naked awareness" points out that your present thoughts will liberate of their own accord and not clutter your mind for too long.