Well said Kevin and others.
We also use one documented procedure to outline both processes with identification and linkage to other initiatives set up by management which also result in corrective or preventive actions (a rose by any other name).
Regarless of any guidance from registrar or consultants each company/organization must evaluate what works best for them. If what someone else would 'Like to see' doesn't work for you - DO NOT DO IT! Just be able to justify sound business reasons for your decision and most will back down.
From my experiences I think there are many unnoticed 'preventive' actions done regularly. As is often the case the paperwork trail and linkage to show improvement is the toughest to provide.
By nature of the focus regarding nonconformances (in either product or processes, they quite obviously get more attention and include supporting documentation).
Actions taken when changing equipment, products, personnel, etc...usually involve multiple run throughs to ensure process runs safely and smoothly producing good product and many efforts will quite naturally go undocumented and often unrealized as preventive actions.
If you have a good company culture and good employees (regarless of position from shop floor to executive office) they will want to work smarter not harder and will add value to the process as they can. Many if you stop and take an interest will tell you "Hey, I changed the way this flows because I saw that _______ might happen and it would _______ (impacting) the product/process".
That's preventive action but quite often isn't enough of a 'WOW' to catch attention and as I said earlier often goes unnoticed.
IMHO this is fine as long as:
1) you identified in personnel training what is critical and cannot be changed without approval (usually well defined between control plan and process and product specs),
2) the person actually has the skills and information to be sure the change won't impact a subsequent process or the product, and
3) communications, at least between all personnel in the process, take place to use best practices across all shifts.
Okay, I'm getting carried away

which is so easy to do! My appologies all.
My best to all,
Eileen