re: my phase hypothesis is dead, and the input puzzle is narrower than

this corpus thought

Last iteration I proposed that the boot title is phase 2 and the
attract-returned title is phase 4 state 0, and that only phase 2 wires up
A -- a candidate answer to the oldest open question in
canary-scripted-input-traps.md. I marked it untested and named a test
that needed reading this+132 at runtime.

There was a cheaper one. The decoded graph says B from the main menu is
the edge 4 -> 0, so the B-returned title IS phase 4 state 0. If that
state were the inert one, A would not work there.

A works. Control first -- A on the boot title opened the menu -- then A
on the B-returned title opened it too. So phase 4 state 0 handles A and
the hypothesis is refuted, one iteration after I raised it. Recorded in
REFUTED under my own name, and the conditional stated: the edge is
decoded, but which title it produces is my inference.

The test earned something better than it cost, though. That page frames
the problem as "the boot title accepts A, a later title does not", and
that is too broad -- the B-returned title accepts A perfectly well, a
case nobody had tried. Only the ATTRACT-returned title is inert. Whatever
causes it is tied to the attract cycle specifically rather than to the
title having been shown before, which is a much smaller haystack.

Also reproduced in passing: 4 s after B the plate is absent and fades in
after, the same near-miss this corpus has already been caught by once.

docs/port/HANDOFF.md

@@ -106,6 +106,10 @@ authored version can be deleted.
   blend of **one element on one screen** (a title glow). Take the stable sort and
   accept that.
 
+* **Ⓑ returns to the title, and that title still works.** Ⓐ on the Ⓑ-returned
+  title opens the main menu — measured, with Ⓐ on the boot title as the control in
+  the same run. (Only the *attract*-returned title is inert, which is an emulator-
+  harness curiosity, not a port concern.)
 * **Menu movement, measured off the running game.** ⬆⬇ move one item per press
   and **wrap at both ends** (5-item main menu and 3-item `EXTRAS` both). ⬅➡ do
   nothing. Ⓑ goes up one level **and restores focus to the item you came from**;

docs/re/REFUTED.md

@@ -35,6 +35,12 @@ neighbourhood, not just the line.
 
 ## Screens, classes and RTTI
 
+* "the boot title is phase 2 and the attract title is phase 4 state 0, and only
+  phase 2 handles Ⓐ" → **mine, and refuted the next iteration.** Ⓑ from the menu
+  is the decoded edge `4 → 0`, and Ⓐ on that returned title opens the menu.
+* "any title after the first one refuses input" → too broad. The **Ⓑ-returned
+  title accepts Ⓐ**; only the **attract**-returned title is inert.
+  [`canary-scripted-input-traps.md`](canary-scripted-input-traps.md)
 * "`sub_821C6458` is `GamePart_Title`'s state machine" → **mine, imprecise.** It
   is the machine for **phase 4** of a five-way outer dispatch at `this+132`;
   phase 0 is the splash. The ten states and eighteen edges are phase 4 only.

docs/re/boot-config-and-gamepart-registry.md

@@ -521,11 +521,13 @@ paths installing the same screen is exactly the shape that would produce that.
 **Candidate:** the boot title is **phase 2**; the attract-returned title is
 **phase 4, state 0**. Only phase 2 wires up the Ⓐ handling.
 
-⚠️ **This is a hypothesis and nothing more** — it is consistent with the draw
-captures and with the phase structure, and it is completely untested. **The test
-is cheap**: read `this+132` (the phase field) at runtime on the boot title and
-again on the attract title. If they differ, the puzzle is solved; if they match,
-this is dead.
+⚠️ **Tested, and dead.** Ⓑ from the main menu is the decoded edge `4 → 0`, so the
+Ⓑ-returned title *is* phase 4 state 0 — and **Ⓐ works there**, opening the main
+menu, with Ⓐ on the boot title as the control in the same run. Phase 4 state 0
+handles Ⓐ, so the two-code-paths explanation is refuted. See
+[`canary-scripted-input-traps.md`](canary-scripted-input-traps.md), which the
+test did narrow usefully: only the **attract**-returned title is inert, not every
+title after the first.
 
 ### ⚠️ One query in this section failed its own control
 

docs/re/canary-scripted-input-traps.md

@@ -660,6 +660,35 @@ state 0 (`sub_821C6458`). Same screen, different code. See
 **Candidate:** the boot title is phase 2; the attract-returned title is phase 4
 state 0; only one of them wires up Ⓐ.
 
-🟡 **Untested.** The cheap test is to read `this+132` at runtime on the boot title
-and again after the attract loop returns. Different values would settle this
-page's oldest question; identical values kill the idea outright.
+### 🔴 Tested the same day — and the candidate is dead
+
+There was a cheaper test than reading `this+132`: the state graph says Ⓑ from the
+main menu goes `4 → 0`, so **the Ⓑ-returned title *is* phase 4 state 0**. If phase
+4 state 0 were the inert one, Ⓐ would not work there.
+
+**It works.** Measured:
+
+| | |
+|---|---|
+| *control* — Ⓐ on the boot title | → main menu ✅ |
+| Ⓐ on the **Ⓑ-returned** title | → **main menu** ✅ |
+
+So phase 4 state 0 does wire up Ⓐ, and "the boot title is phase 2, the returned
+title is phase 4 state 0, only phase 2 handles Ⓐ" is **refuted**. (Conditional on
+the graph reading that Ⓑ lands in state 0 — that edge is decoded, but which
+*title* it produces is my inference.)
+
+### ✅ What the test did establish — the puzzle is narrower than this page says
+
+This page frames the problem as *the boot title accepts Ⓐ, a later title does
+not*. That is too broad. **The Ⓑ-returned title accepts Ⓐ perfectly well** — a
+case nobody had tried. Only the **attract-returned** title is inert.
+
+So whatever makes the title stop responding is tied to the attract cycle
+specifically — the movie playing and coming back — not to "the title has been
+shown before". That is a much smaller haystack than the one this page has been
+pointing at.
+
+⚠️ Also reproduced in passing: 4 s after Ⓑ the plate is **absent** (169 plate
+pixels), and it fades in after. A test that samples too early will read the
+returned title as plate-less, which this corpus has already been caught by once.