No, not that kind of repetition!
This is one of those things where they could have given it a better name, but they went with the acronym instead. They say repetition, but they really mean consistency. What it means is that all your headings should look the same as all your other headings, all your sub-headings should look the same as all your other sub-headings, and all your body text should look the same as all your other body text.
It means that once you establish a certain style for your document, you should stick with that style. Otherwise, your document looks like it's got multiple personalities. That's not a good thing for a document. It should be nice and cohesive, so that people can look at it and figure out what's going on.
Repetition does not mean that everything in your document should be exactly the same. That would contradict Contrast. (See part of my issue with the CRAP principles is that teachers like to present them in ways that make it seem like they contradict each other.) Titles should still look different from headings, headings should look different from sub-headings, and sub-headings should look different from body text.
Getting back to that road sign analogy, what repetition means is that stop signs should look like stop signs, speed limits should look like speed limits, and road names should look like road names. If someone put up a sign that said "Grand Avenue" but looked like a Yield sign, no one would know what to do with it. If someone wrote "STOP" on a sign that looked like a "No Parking" sign, nobody would stop.
So, we call it Repetition for the sake of a handy little acronym to help us remember how to design a document, but we really mean consistency.