This guy claims to be a fully-enlightened Buddha, an emanation of Vairocana. His adoption of Tibetan flourishes has been done without much actual input or recognition from Tibetans. Wikipedia (which is not as informative as it might be) notes (unproven) charges of sexual abuse, made by an ex-member in the USA. Here's an article with concrete, neutral details about the sect: http://taiwanpedia.culture.tw/en/content?ID=1830
Where does it say he's an emanation of Vairocana? He's supposed to be an emanation of Padmakumara. One of his masters was Guru Thubten Daerje. I have seen the liturgy followed by traditional Tibetan Buddhists. Starts with invocation, visualization of buddha, dharma, sangha (with prostrations). Offerings to the triple jewels, visualization of the merging with one's personal deity, with use of mantra and mudras. The liturgy advocated by Sheng Yen Lu in the True Buddha School only differs slightly in pronunciation of the mantras, with slightly different formations of mudras and a half prostration instead of full prostration. In short, it's the same practice, with some minor changes here and there. They also employ the same tantric implements Tibetan Buddhists do, with use of vajra bell, vajra staff, horns, drums, bells, and other.
If anyone has a copy of traditional Tibetan liturgy from Yellow Hat Sect to share, you can put it next to the True Buddha School liturgy and compare it for yourself. You can view/download the True Buddha School liturgy for yourself, just Google it. It starts with invocation of Buddhas, visualization of purification of body, speech and mind, offerings to the triple jewels, dharma protection, chanting of High King Sutra, visualization of personal deity and merging into one, then silent meditation with breathing exercises, lastly, supplication. The Tibetan Buddhist daily practice does not differ drastically from this.