diff --git a/docs/port/f6-what-starts-the-sweep.md b/docs/port/f6-what-starts-the-sweep.md
index 3d02c00f..1615498e 100644
--- a/docs/port/f6-what-starts-the-sweep.md
+++ b/docs/port/f6-what-starts-the-sweep.md
@@ -559,3 +559,39 @@ pins the clock cannot answer a question about the clock running*, and *an
 instrument going quiet is not the subject going quiet*. The second is the same
 shape as the Decoder's own absence-of-a-quad bug — a count of zero says only that
 nothing reached the reader.
+
+---
+
+# ✅ Out-of-sample: what the port ships was in the passing half
+
+The Decoder pre-registered six predictions and tested them on a fresh boot that
+had no hand in deriving them. **Three failed.** Audited here against what this
+port actually authors, and the answer is **nothing to change**:
+
+| their prediction | fresh boot | does the port carry it? |
+|---|---|---|
+| leaf period ratio 1.200 | 1.1753 ✅ | **yes** — this is `rate = 0.5` |
+| strip size ratio 1.333 | 1.3009 ✅ | yes, as element identity |
+| pulse / sweep loop 0.100 | 0.0963 ✅ | yes, `looping_focus_records` 120 |
+| pulse amplitude ≤3 levels | 8.73 🔴 | no |
+| `ptcopyright` ramp ratio 0.733 | 0.550 🔴 | no |
+| sweep leads plate 0.138–0.141 | **0.0996** 🔴 | **no** — grepped, absent |
+
+`authored/rendering.json` `leaf_clock` is `{start_units: null, rate: 0.5}` and
+nothing else. No separation constant exists in `authored/`, `tools/port/` or
+`port/scripts/`.
+
+📌 **That split is not luck and is worth naming.** Everything the port adopted is
+either **declared on the disc** (the parent gate, the 120-unit pulse loop, the
+600/720 leaf periods) or **corroborated by three independent legs** (the rate).
+Every failed prediction is a figure derived from *relationships between elements
+measured in a capture* — the class with no declared counterpart, which
+`check-authored-vs-declared` says out loud it cannot arbitrate. The rule "adopt
+what the disc declares, or what three unrelated things agree on" selected exactly
+the surviving half without anyone knowing which half that would be.
+
+⚠️ And the Decoder reports that `check_labels.py` — offered last iteration as the
+mechanism for capture-only labels — **fails its first independent test**: two of
+its four checks fire on a third capture, having been validated on the two that
+produced the labels. An instrument validated on its own training data. Nothing
+here depends on it, but it is not a mechanism this port should lean on either.