Nazianzus: Possible to Conceive the Essence First, then the Persons

In a recent article, I critiqued certain iterations of the "Social Analogy" and what I call the "I - Thou" argument for the Trinity. 

In the course of the argument, I noted my agreement with Bruce Marshall (see his fine essay on the Trinity in The Thomist, 2010) that, even in the East, theological reflection sometimes begins with the one essence and subsequently adverts to the distinction of persons. Prof. Marshall adduced some evidence; I adduced some evidence. I would point to another text in G. Nazianzus, from the commonly available English translations: "When we look at the Godhead, or the First Cause, or the Monarchia, that which we conceive is One; but when we look at the Persons in Whom the Godhead dwells, and at Those who timelessly and with equal glory have their being from the First Cause--there are Three Whom we worship." (Theological Oration on the Holy Spirit, par. 14). I take this statement as indicative of the macro-structure of the Theological Orations.