The refined vacant-see position formulated by the Dominican theologian Michel-Louis Guérard des Lauriers (a former Écône professor) in the Cahiers de Cassiciacum (1979–81): the occupant of the see is pope 'materially' but not 'formally' — retaining the designation but not the authority. Followed today by institutes descending from his Thục-line consecration (1981).[1]