Scope
Reference Series 6 was issued to clarify a recurring field observation: an element moved a short distance may remain visible, accessible and apparently available while no longer occupying an equivalent position.
A nearby position is not necessarily an equivalent position.
Method
The clarification directs reviewers to consider access envelope, approach, return path and persistence before treating a nearby position as an acceptable variance. It remains a historical reference because the language is concise and continues to explain why positional variance cannot be considered as distance alone.
The principle was incorporated into the 2006 PCP field revision and remains represented in MCS-01-24.
History
Series 6 is superseded as a standalone field reference. Its content is active through PCP-87-24. No replacement document removes the original distinction; the distinction was carried forward into a broader method.
Related publications
PCP-87-24 · MCS-01-24 · RS-04-91