a·naph·o·ra [...]
        –noun
        1.  Also called epanaphora. Rhetoric. repetition of a word or words at the beginning of two or more successive verses, clauses, or sentences. [...]
        2.  Grammar. the use of a word as a regular grammatical substitute for a preceding word or group of words [...]
        3. (sometimes initial capital letter) Eastern Church. [...]

Aif and awhen use meaning 2, while this essay probably means 1.