The framing of the essay around learning through "grunt work" is not deep, it's simply that this specific phrase appeared in two of the sources. Anything that looks like insight is plagiarised directly from the sources in some fashion. I've covered in my evidence the pivot phrases where direct summaries of the essay incorrectly appear to transition to the author's own ideas, but there are parts right through the essay that come from the sources. No deep thinking by the prompter required.