And I believe that this is not a listing and labeling instruction. It is just an manufacturer's attempt to sell more product. I am sure that there was not any testing that showed a safety hazard if you re-identified the conductors.
This issue of 110.3(B) has gone way overboard. Where do we draw the line? Why does UL get to tell us what 110.3(B) means? They are not the AHJ and have not code interpretation authority.
110.3(B), is limited, in my opinion, to things that are an actual part of the listing and labeling. If the instruction is not in the White Book, it is not 110.3(B).
The listing is the actual testing of the product and the labeling is the sticker or other identification on the product that indicates the product has been listed.