For practitioners on the paths of Dzogchen and Mahamudra, one of the greatest joys is to personally receive oral instructions from a realized teacher. The excitement of being able to train based on that advice is further enhanced by the stimulation and support that guidance manuals provide. All of the selections presented in Perfect Clarity offer incredible teachings that are inspiring and vital. Pith instructions are so simple and direct that we can easily apply them without fear of mistakes.
These days, the most effective style of teaching is not lengthy scholarly explanations but rather direct guidance manuals The Dzogchen tantras themselves were written in a style that shrouds and conceals the meaning so that only a master who is extremely well-versed in oral instructions and treatises is able to clarify the meaning. On the other hand, based upon oral instructions a guidance manual is a short, comprehensive teaching written in a clear and simple manner. Such summaries of the Mahamudra and Dzogchen teachings contain all the teachings that a worthy practitioner requires to reach the state of primordial enlightenment in this very life.
Tulku Urgyen Rinpoche
The amazing collection in Perfect Clarity is rounded out by an introduction by Tulku Urgyen Rinpoche, a preface by Marcia Dechen Wangmo, biographical data of the authors, a glossary, line drawings and photos and Tibetan source material references.

"Dispeller of Obstacles" is the first in a new series that will include video, audio, photos, and commentaries to support practice and is the heart essence of the accomplished 9th-century master Padmasambhava. This hidden treasure is a revelation with a rich history that is explained in the book. In addition to the root text and classical commentaries by Chokgyur Lingpa and Jamyang Khyentse Wangpo, the treasure-revealers themselves, there are also explanations by modern-day masters such as Tulku Urgyen and Orgyen Topgyal Rinpoches. This extensive cycle contains teachings and practices for the preliminaries up to and including Dzogchen. Linking to a fresh treasure has the power to imbue us with hot and juicy blessings that invigorate our being and generate devotion and joy. Just as we prefer to have fresh food, these treasure teachings are endowed with a very special quality that has not been interpolated by anyone else, but has come directly from Padmasambhava by means of one of his disciples appearing as a present-day incarnation. The teaching is then spread to people for their immediate practice.

The Light of Wisdom, the Conclusion, presents detailed explanations of the activities of a Vajra Master and Buddhist practices to clear away hindrances on the path and enhance realization. The book is a combination of three texts:
The root text, The Gradual Path of the Wisdom Essence is oral instructions of Padmasambhava, recorded by his chief female disciple, Yeshe Tsogyal. Padmasambhava established the Buddhist doctrine in Tibet during the eight century. He concealed teachings in the form of hidden treasures, to be revealed at an appropriate time in the future. The Light of Wisdom by Jamgon Kongtrul, one of the most prominent Buddhist masters of nineteenth-century Tibet, is an extensive commentary on this sacred scripture. Entering the Path of Wisdom consists of annotations on the commentary by Jamyang Drakpa, a student of Jamgon Kongtrul, dictated to Jokyab Rinpoche.
The root text of Lamrim Yeshe Nyingpo, a terma revealed by the great treasure-finder Chokgyur Lingpa, and its commentary by Kongtrul Rinpoche, the great translator in person, form together a complete scripture that embodies all the tantras, statements and instructions of the Nyingma School of the early translations, which is most rare to find in the past, present, or future. ...I find it important that all Dharma practitioners study and reflect upon this book.
? Kyabje Dilgo Khyentse Rinpoche

It is correct that it will be quite difficult to practice the entire Gradual Path of the Wisdom Essence, so you should use what is directly appropriate for your training. It is never said that you should practice an entire root text as Light of Wisdom contains the complete path for different kinds of individuals, both of Hinayana, Mahayana and Vajrayana. But since its title is the Wisdom Essence, it means that its ultimate practice is Dzogchen.
? Kyabje Tulku Urgyen Rinpoche