Again, I used a slightly older model in the same series, Opus 4.6. It read the same prompt without any problem whatsoever. Also, a (non-Opus 5.5) Claude wrote the prompt in the first place.

Opus 5.5 literally refused to work OR EVEN TELL ME WHAT I'D "SAID" when it read that prompt.

Nothing to do with skill or the user at all: same exact prompt, three different models ... two worked, one didn't.