Nichiren Shoshu adopted Shingon Guru [Yuiga] Yoga and SGI ran with it.

"When the priests and lay believers of the faith of Nichiren Shoshu have the occasion to be in the presence of the high priest, with palms pressed earnestly together in sincere gratitude, we pay prayer-like reverence to him as the Master who embodies the Living Essence of the Body of the entirety of the Law of all existence, which has been passed down through the generations since the lifetime of the Daishonin. . .In short, with perfectly sincere faith and self-imposed strict obedience, we should hold the high priest's instruction in deepest reverence -- and we must realize that it is right there that the great, direct path of the true relationship of unfiltered, unrestricted faith between Master and disciple, which leads to ultimate enlightenment in this lifetime, is to be found." (Dai Nichiren Special Edition (II) 1991 pp. 13-14)