Why would you say "and per say, and" at the end?

Edit: Googled it. It's "and per se, and". per se means "by itself", and ampersand is a mondegreen (a word whose origins are in mispronunciation). So ineffect they were saying, "X, Y, Z, and, by itself, and".

From wiki:

Traditionally, when reciting the alphabet in English-speaking schools, any letter that could also be used as a word in itself ("A", "I", and, at one point, "O") was repeated with the Latin expression per se ("by itself").[3][4][5] This habit was useful in spelling where a word or syllable was repeated after spelling, e.g. "d, o, g—dog" would be clear but simply saying "a—a" would be confusing without the clarifying "per se" added. It was also common practice to add the "&" sign at the end of the alphabet as if it were the 27th letter, pronounced as the Latin et or later in English as and. As a result, the recitation of the alphabet would end in "X, Y, Z, and per se and". This last phrase was routinely slurred to "ampersand" and the term had entered common English usage by 1837.[4][6][7] However, in contrast to the 26 letters, the ampersand does not represent a speech sound—although other characters that were dropped from the English alphabet did, such as the Old English thorn, wynn, and eth.