diff --git a/flow-state/MIGRATION.md b/flow-state/MIGRATION.md
index 0317484..550dcd1 100644
--- a/flow-state/MIGRATION.md
+++ b/flow-state/MIGRATION.md
@@ -206,21 +206,35 @@ looks because the scene it probes is picked from the migrated set and changes
 between runs — Constellation, then Metaballs, then Floating Geometry — so read
 it as "comparable to the container" rather than as a precise ratio.
 
-End to end, song variety across twelve songs before and after the epic:
+End to end, song variety across twelve songs — and a warning about how to read
+it. A single run after the migration gave separation 0.38. Three runs give:
 
 ```
-                 floor    observed   separation
-before          0.1449      0.1508   not computable (the reference sat below the floor)
-after           0.1185      0.1376   0.38
+separation   0.314, 0.555, 0.065      mean 0.311, half-range +/-0.245
+floor        0.1073 +/-0.0145
+observed     0.1162 +/-0.0185
+ceiling      0.1434 +/-0.0000
 ```
 
-The floor fell and the gap widened, which is both halves of what the inversion
-was supposed to buy. Every structural block moved with it — scale 40→59%,
-orient 65→89%, layout 60→111%, texture 89→81%, motion 53→65% of reference.
+**Do not quote the separation figure.** It is a ratio of two small differences —
+`(observed - floor) / (ceiling - floor)` — and the numerator here is 0.0089
+while each of its terms carries an error bar twice that size. The ratio is not
+measuring the generator at this sample size, it is amplifying the noise in both.
+The 0.38 that appeared in a single run was meaningless, as was reporting it.
 
-Coupling did not move: -0.09, still indistinguishable from zero. Whether a song
-LOOKS different in proportion to how it SOUNDS different remains unsolved, and
-nothing in the migration addressed it.
+What can be said: the ceiling now sits reliably ABOVE the floor, with zero
+variance across runs, where before the epic it landed underneath and the ratio
+was not computable at all. That is a change in kind and it is solid. The
+magnitude is not.
+
+The trustworthy measurement in this harness is the DECOMPOSITION, not the
+top-line ratio. `decompose` has a noise floor of exactly 0.0000 and effects an
+order of magnitude larger than any drift, because it compares renders directly
+rather than dividing differences of aggregates. Steer by that.
+
+Coupling did not move: -0.02 +/-0.03. Whether a song LOOKS different in
+proportion to how it SOUNDS different remains unsolved, and nothing in the
+migration addressed it.
 
 Read that with its caveat: the stage set changed underneath the measurement, so
 part of the jump is that Metaballs expresses a cast more strongly than