Problem: New rule has no impact on existing diagrams
After creating some Schematic diagrams, a rule is configured for the Diagram Type using the Schematics Designer. When an existing diagram is reopened, the nodes are not reduced.
Rules are only applied when diagrams are created and/or updated. If a rule is added after a diagram is created, that diagram needs to be updated to reflect the change.
Solution or Workaround
Open the diagram in ArcMap and run the Update function.