Corrective and Preventive actions may very well have serial numbers attached to them for the purpose of tracking and control. I don't really believe that something as key to a system as written procedures and instructions shouldn't have their very own numbers. A discrete number avoids all confustion. I am amazed at the ease with which people in industry at all levels learn to talk in part numbers - allowing meaningful communication among people with differing language abilities. Numbering systems require no new skills but rather build on established industrial language patterns.
Departments have numbers, operations have numbers, people have numbers.
No change of paradigm required. Based on what is being said, at some level of development numbering systems must not make sense - but I have trouble imagining such a level. My counsel to Megan and others is that numbering systems do make sense and should not be abandoned unless you know you have a better way.