Thank for the link but that seems misleading or just wrong. “A per se A” means

    “a” (per se = by itself = as a letter) [spells the word] “a”
    

Nobody would recite the alphabet as

    a per se a, bee, …, aitch, i per se i, jay, …

and ending with

    … zee and per se and

means

    … zee and “&”

It was not, at claimed there,

    Y, Z, and & per se &

In that case the modern name would be _andampersand_!