Brendan,
[Warning: spoiler alert]
I saw a PT-themed crossword in recent memory (past 6-8 months? not sure), iirc in a prize or holiday puzzle, can't recall the paper. Agreed this is the first time I've seen it in every clue.
Funny, the theme only registered for me when I realized that a key word (ELEMENT) had appeared as an answer in a Friday crossword (paper omitted) I solved.