The mechanism seems to survive editing. The extreme probabilities get a little less extreme, but are still extreme enough to be distinctive.
But it wouldn't survive paraphrasing, because the output would be entirely human and the token correlations would disappear.
It might not survive referencing if only a sentence or two is used.
The practical issue is how true the claims are. It's one thing to create a proof of concept, another to see how it works in use.
And this is potentially catastrophic for code, because the grammar and word choices of code are completely different and more fragile than standard English.
Similarly, if you quote someone word-for-word, you wouldn't anticipate their words to be flagged as Claude content, but if someone memorized Claude output word-for-word. That would still be classified as a Claude output.
Going forward you could categorize the influence of Claude on a population based off a percentage match between their spoken words with the LLM prose.