I must be missing something - what is the plausible deniability? If someone does a raw text dump of a pdf and gets the hundred new keywords, surely someone would recognize what you did?
Or do you just mean, it will silently pass the white text test?
Or do you just mean, it will silently pass the white text test?
I don't think "humans" look at raw text dumps of PDFs do they? I mean, I don't know, when I've interviewed people I only looked at the rendered output. The goal would be to full the robots; for the visible text I would be complete honest.
Again, I never actually did it.
As to the text dumping -I have no idea. I could believe some of the HR screening tools select all text and dump into some structured fields for review. Probably not, and the trick will go completely undetected.
And I wonder if this argument would fly, e.g. in a court of law: "the information I would like to convey to HR is the one that is readable by human eyes when my CV is rendered by a normal PDF reader (e.g. insert known PDF readers here), anything that is not readable by the human eyes should not be considered part of my CV.".