No, I never believed this. I knew Zemey Tulku. However, I do not believe the information contained in The Yellow Book. I don’t know the real reason for his writing this book. Maybe this was his view and he was trying to prevent Gelugpa Lamas from engaging in Nyingma practices. There are two reasons why I don’t believe this. One is that Dorje Shugden never harms any sentient being because he is a Buddha, an enlightened being. He has compassion for all living beings without exception, even those who try to harm him. The second reason is that the list of Lamas in The Yellow Book supposed to have killed by Dorje Shugden never received any harm from any spirit because they were sincerely practicing refuge in Buddha, Dharma and Sangha.
In many holy scriptures of Sutra and Tantra it says that those who are sincerely taking refuge in Buddha, Dharma and Sangha, will never receive harm from spirits. We have this guarantee from Buddha if we sincerely practice refuge. I understand that The Yellow Book causes many Nyingmapa practitioners to become unhappy with Dorje Shugden, and because of this they do not appreciate Dorje Shugden practitioners and sometimes even criticize them. This causes the development of disharmony within the Mahayana Buddhist community. As we know, our harmony is important. We Buddhists need to show a good example, we should not argue with each other or criticize each other. We should practice our own tradition purely but respect other traditions. We should never try to destroy the spiritual life of others. Although some people say ‘I am Nyingmapa’, ‘I am Gelugpa’, this is just a different way of presenting and practicing Dharma. The real essence is the same. So I would like to suggest to everybody to forget The Yellow Book. The Yellow Book was not written by Buddha, so why should we believe this? (Geshe Kelsang Gyatso, alt.religion.buddhism.nkt, 24 November 1996)
Although Je Phabongkhapa’s view is that Dorje Shugden is an enlightened being, the 13th Dalai Lama, using his political power, did not allow Je Phabongkhapa to publicize this view, so he had to accept the lower position of Dorje Shugden. Therefore, at that time Gelugpa practitioners lost their freedom to say publicly that Dorje Shugden is an enlightened being. To the majority of ordinary Tibetans Dorje Shugden appeared as a worldly spirit. At that time there were many stories and rumours about how Dorje Shugden would help some people, harm others and so forth, all according to the ordinary appearance of the majority of people, most of whom were very superstitious. The stories mentioned in Zemey Tulku’s ‘Yellow Book’ are just superstitions. He was not necessarily expressing his own view in this book, but telling about many different superstitions according to ordinary people’s appearance of Dorje Shugden. Of course the view of Dorje Shugden as a harmful spirit was neither Trijang Rinpoche’s view nor was it Je Phabongkapa’s. (Geshe Kelsang Gyatso, talk.religion.buddhism, 19 December 1997)