Full recorded H2-089 profile through q=M2/M1=1:
- SOURCE_ONLY_LEGACY homogeneity drift: 50%
- PAIR_TOTAL_EVERYWHERE: numerical zero
- SPLIT_SOURCE_FIELD_PAIR_ORBIT: 4.257748%

The default Laboratory wrapper runs the smaller historical validation profile, where finite-resolution Split drift can differ (about 4.93% in the current validation run). The selection-critical result is unchanged: Pair Total remains at numerical zero while the alternatives drift. Use `python lab_test.py --full` for the publication-scale profile.
Browser preserved q ladder: SOURCE_ONLY reaches -50.0000% at q=1; PAIR_TOTAL remains numerical zero; SPLIT reaches -4.2577%.
