Cleenewerck's main ideas are presented in his comprehensive study of the historical and theological causes of the current separation between Roman Catholicism and Eastern Orthodoxy (His Broken Body – Understanding and Healing the Schism between the Roman Catholic and Eastern Orthodox Churches). Like John Zizioulas, he is an advocate of Eucharistic ecclesiology which he articulates as Holographic anesthesiology. The outline and implication of this model were published in the Journal of Ecumenical Studies in 2010. He is a proponent of non-partisan ecumenical dialogue with the ideal of a return to the basics of pre-Nicene orthodoxy.