[1.2.397] Demon Slayer (3)

I don't see why you couldn't get them on the new rank, unless you expect all your lines to be primary lines.

umm...
tell me, when was the last time you got "Feel angry for 10 seconds" on a unique helmet?
Oh, that's right.
Never.
Because the data for potential makes it so that you can only get the potential lines that are listed at that tier. You can't get things like happy for a certain amount of time on a unique equip, because that's only for rare.
Same applies in this situation.