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F2_cobol_legacy_v1: IRDME on a 14-program COBOL banking application finds r(PERFORM↔COPY)=0.807 (p=0.002) vs r(PERFORM↔data_field_sharing)=0.119 - the Functional Proximity Law holds in 50-year-old procedural mainframe code. Two structurally dormant programs appear as rank #2-#3 hubs in data_field_sharing despite zero PERFORM calls. Rank gap=11 each. Multilayer rank divergence identifies components that are operationally peripheral in execution topology yet central in shared-state topology.

post.php ranks #19 in import graph centrality but #4 in co-change centrality — a rank gap of 15. It is structurally peripheral, behaviourally central. Every migration that ignores this distinction will break.