port: census every layerless full-screen element; the forced-backdrop quantifier misses nothing in GP_TITLE

Tries to refute the rule by SUFFICIENCY rather than correctness: a strict
'all others visible' quantifier fails quietly, so the question is whether any
full-screen opaque backdrop misses the bar and keeps hiding its screen.

None does. Everything that fires is at 100% of others; everything that does not
is at 13-47%, and pteff02 never reaches alpha 255 at all. No borderline case.

Reproduces the Decoder's second control exactly (pteff00 forced below 3 of 23)
and shows their palogo_eff0 span gap is not a constant offset -- 211 is the
number our developer_logos row does reproduce.

Also retires the 'loading screen fade quad rests OPAQUE BLACK' row: resolved by
the rule, and it recorded rest.t as 38 where it is 0.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF

docs/port/BLOCKED.md

@@ -124,7 +124,7 @@ HANDOFF.
 
 | P7 / naming — the four unnamed builds | **which locale and variant is each of `GP_TITLE` entries 0, 1, 12, 15?** | — | 🟢 **found by the port, not blocking, and handed over.** All four are **loading screens**: every element in all four is named `pgloading_*` (`pgloading_processing.png`, `pgloading_circle1`, `pgloading_delta`, `pgloading_ring`), and `LOADING` is one of the three screen names the Decoder read out of `sub_821C6458`. They export today as `build_00`, `build_01`, `build_12`, `build_15`. Two variants: 0/1 carry 7 elements, 12/15 carry 10 (adding `pgloading_eff00`, `pgloading_loop5`, `pgloading_baseeff`). The archive's own pairing — adjacent for 2/3, `+3` for 4…9 and 10/13, 11/14 — suggests 0 is the twin of 1 and 12 the twin of 15, but **which member is which locale is an inference and the port has not named them on it**. Naming is cheap for the Decoder and a guess for the port. |
 | P7 — what fills the 4.5 s before `S00A` | **is the LOADING screen what appears between the save slot and the new-game movie?** | Q4 + Q9 | ❔ **not observed, and the port has not assumed it.** Q9 measures `S00A.wmv` starting ~4.5 s after Ⓐ on the save slot. The run that would have shown what is on screen for those 4.5 s hit the documented `sub_823070B0` cache crash after `SELECT DATA`. `GP_TITLE` carries a loading screen (row above) and 4.5 s is about the right shape for one, and that is **exactly why it is written here and not in `flow.json`**. Settled by one run that reaches the movie without crashing. |
-| P3 — a second `rest.t` casualty | **the loading screen's fade quad rests OPAQUE BLACK** | — | 🔴 **noted, not fixed.** `pgloading_eff00.prm` on entries 12/15 is a 1280×720 black quad whose group is `0xff000000` at t=38, `0xff000000` at t=48, then `0x00000000` on the untimed final — black, held, *then* clear. Its `rest.t` is **38**, where it is fully opaque. So a port that draws this screen at its `rest` draws **a black rectangle over the whole loading screen**. This is the same `settle_time()`/`rest.t` problem as the row below, in a form where it hides the entire screen rather than dimming it — and it will bite whoever first draws a loading screen. |
+| ~~P3 — a second `rest.t` casualty~~ | ~~the loading screen's fade quad rests OPAQUE BLACK~~ | — | ✅ **resolved 2026-08-29 by the forced-backdrop rule, and this row carried a stale number.** The quad still rests opaque — that part was right — but it no longer *hides* anything: it is a layerless full-screen element opaque across a span containing all 9 others, so it is **forced to paint first** and the loading screen draws over it. At `--pose=rest`, `build_12`/`build_15` went from **mean 0, the whole screen black** to mean 1.95 with **59 530 non-black pixels**. ⚠️ Two corrections to what this row said. Its `rest.t` is **0, not 38** — stale since the keyframe-layout correction (`formats-pin-2026-08-29c`) timed every pose; the group is `0xff000000` at t=0 **and** t=38, then `0x00000000` at t=48, so the conclusion held while the number did not. And the general `rest.t` complaint is **not** resolved: an opaque element at its rest instant is still opaque, and this one stopped mattering only because it is a full-screen backdrop. **The row below still stands for anything that is not.**
 
 | ~~P6 — runtime headroom~~ | ~~the Master bus clips~~ | — | 🟢 **withdrawn by the port, 2026-08-29 — it was my own overstatement.** Filed 🔴 twice on a peak reading of 0.0 dBFS. Measured properly: **43 samples at full scale in 5.9 s and 24 in 98.5 s, longest clamped run 0.25 ms** — the disc's own `confirm` cue touching the ceiling on a transient, possibly only in the recording's 16-bit conversion since Godot mixes in float. Not a defect, and nothing is changed: attenuating to buy headroom would be an unmeasured level decision of exactly the kind this port refused for the BGM loop point. **A peak reading is not a clipping measurement** — one sample at 0 dBFS and two seconds of square wave give the same number. |
 | Modding — rule 4 | ~~base-and-overrides is unimplemented~~ | — | ✅ **implemented 2026-08-29, and it was not blocked on anybody.** `MODDING.md` calls it a constraint on the exporter *today*; nothing read `data/mods/` for eight milestones. `ExportTree.resolve` now shadows by path for every asset kind, each replacement is logged as it is read, and `.gitignore` excludes the directory's contents — a mod is usually an edited game asset, and that directory was the one place git would have taken one. ⚠️ The `export/` vs `data/base/` naming split between `PORT-MISSION.md` §3 and `MODDING.md` is **raised, not resolved**: only the human changes a mission. |

docs/port/DECISIONS.md

@@ -4993,3 +4993,45 @@ hold directly: the frame is constant from t=30 to t=60 with the timeline running
 It also explains 36 builds the Decoder had filed as "coming out one colour":
 `pzeff00.prm` is forced first in 32 of 32 of them. Those were wiped by our own
 sort.
+
+## Refutation attempt — the forced-backdrop rule's quantifier, and whether it misses a case
+
+The rule fires only when **all** other elements are visible during the opaque
+span. That is a strict quantifier, and a strict quantifier fails quietly: an
+element that is a full-screen opaque backdrop but misses the bar by one dark
+element would keep its layer-key position and go on hiding the screen, exactly
+the defect the rule was written to fix. So the question worth asking of somebody
+else's rule is not "is it right" but **"is it enough"** — and that one I can test
+without an oracle, over every layerless full-screen element in `GP_TITLE`.
+
+| screen | element | opaque instants | others visible | forced |
+|---|---|---|---|---|
+| `build_12`, `build_15` | `pgloading_eff00` | 39 | **9 / 9** | ✅ |
+| `developer_logos` ×2 | `palogo_eff0` | 211 | **6 / 6** | ✅ |
+| `publisher_logo` ×2 | `palogo_eff0` | 256 | **2 / 2** | ✅ |
+| `title`, `title_jp` | `pteff00` | 2 | 3 / 23 | — |
+| `main_menu` ×2 | `pteff00` | 2 | 7 / 15 | — |
+| `extras` ×2 | `pteff00` | 2 | 5 / 17 | — |
+| every screen | `pteff02` | **0** | — | — |
+
+**The rule survives, and the margin is the reason.** Nothing sits near the
+boundary. Every element that fires does so at **100 %** of the others; every
+element that does not is at 13–47 %, and `pteff02` never reaches alpha 255 at all,
+so no quantifier could fire on it. There is no borderline case in this archive
+for a stricter or looser reading to disagree about — which is the answer I could
+not have gotten by re-checking the six screens where it already fired.
+
+It also reproduces the Decoder's **second** control number exactly: they report
+`pteff00.prm` forced below **3 of 23**, and `title` measures 3 of 23 here. With
+their opaque-instant count of 2 already matched, two of their three published
+figures for that control now come out of an independent implementation
+unchanged. The third — `palogo_eff0`'s 211 against our 256 — remains the span
+disagreement filed in `BLOCKED.md`, and note that the 211 is the number our
+`developer_logos` row *does* reproduce. That is worth saying plainly: **the
+disagreement is not a constant offset**, so "they stop 45 instants early" is not
+the explanation, and whatever it is differs per screen.
+
+⚠️ What this does **not** test: whether the rule is right about the 50 elements it
+calls constrained-but-not-forced, and whether alpha-over is the blend mode. Both
+are the Decoder's to settle. It tests completeness within one archive, which is
+the half I can reach.