re(ui): the eff-name implication for bit 0x02 is refuted disc-wide

Last iteration I killed the biconditional and reported that the one-way
reading survived: all 10 bit-set sprites on GP_TITLE build 4 are eff
names, so "bit set => eff name". Checked over the disc, that is false.

  sprites with a resolvable preceding name   14 709
    bit SET   & name has 'eff'                2 338
    bit SET   & name lacks 'eff'              2 657   <-- counterexamples
    bit clear & name has 'eff'                1 399
    bit clear & name lacks 'eff'              8 315

  P(eff | set)   = 0.468
  P(eff | clear) = 0.144

The implication fails more often than it holds. What survives is an
association -- 3.3x enrichment -- and build 4's 10/10 was a local naming
habit in an 18-element bundle, not a format rule.

The counterexamples are the useful part: pv_loading_ring0,
pv_loading_light0-3, pv_loading_line, px_bunk_line, px_top_extra. Rings,
glows, lights, thin lines -- effect-like artwork that does not carry the
eff naming convention. Consistent with the bit marking effect sprites by
authoring intent rather than by name, which is a description and not a
decode, and is labelled as such.

Names here come from the string immediately preceding each T8aD,
validated 17/18 on build 4 against the RATC child order; the single
mismatch is the known pteff04.t32 -> registered as 8AX case, so this is
the element (opt) name rather than the sprite's registered name. That
mismatch is itself an independent confirmation of the 8AX finding,
reached from the opposite direction.

METHOD: a pattern perfect on one screen can be near-chance on the disc;
and when an association survives a refuted implication, the
counterexamples are the finding.

docs/port/HANDOFF.md

@@ -120,7 +120,7 @@ authored version can be deleted.
   ⚠️ **Correlation only — untested.** Nothing yet shows it *means* additive; the
   test is to blend bit-`0x02` sprites additively and re-correlate the title
   against the capture. Note `ptlogo_back2eff` is `0x8830` despite its name, so
-  this is a field and not a naming pattern. ❔ Not diagnosed — but two candidate meanings are now dead: **not** "the name contains `eff`" (`ptlogo_back2eff` is an `eff` name with the bit clear — confirmed by a validated name→header pairing, not a size guess) and **not** "the element is transient" (`pteff03`/`pteff03a` carry the bit and persist to `t=250`). ⚠️ Practical note for an asset pipeline: `T8aD` headers appear in **RATC child order** (18/18 verified on build 4 against decoded dimensions), which is the only sound way to attribute a header to a name when two sprites share a size — and two here do.
+  this is a field and not a naming pattern. ❔ Not diagnosed — but two candidate meanings are now dead: **not** "the name contains `eff`" — and not even the one-way "bit ⇒ `eff` name", which held 10/10 on the title but fails on **2 657 of 4 995** bit-set sprites disc-wide (`P(eff|set) = 0.468`). What survives is a 3.3× association, and the counterexamples are rings, glows and lights — effect-like art without the naming convention and **not** "the element is transient" (`pteff03`/`pteff03a` carry the bit and persist to `t=250`). ⚠️ Practical note for an asset pipeline: `T8aD` headers appear in **RATC child order** (18/18 verified on build 4 against decoded dimensions), which is the only sound way to attribute a header to a name when two sprites share a size — and two here do.
   ⚠️ **The rotated draw is NOT the swoosh.** It was identified as the swoosh by
   elimination; that is **refuted** — its quads span y −209…925 in screen space,
   the swoosh is a band at y 126…360. ✅ **It is the two `ptloop` sweeps**

docs/re/METHOD.md

@@ -687,3 +687,16 @@ agent's loop prompt, i.e. nowhere durable. See [`README.md`](README.md) for the
   "the bundle stores this texture twice". Pixel-comparing them gives max abs diff
   **21**: two different renditions of one image. Three matching summaries over
   300 000 pixels is weak evidence of identity; the comparison costs one line.
+* **A pattern that is perfect on one screen can be near-chance on the disc.** The
+  `0x02` bit matched `eff` names 10/10 on `GP_TITLE` build 4, which is exactly
+  the sample size that makes a rule feel found. Disc-wide it holds 46.8 % of the
+  time — the build's artists simply named their effect sprites consistently. An
+  18-element bundle cannot distinguish a format rule from a local naming habit;
+  before reporting an implication, run it over the corpus, not the example that
+  suggested it.
+* **When an association survives a refuted implication, the counterexamples are
+  the finding.** The bit is 3.3× enriched for `eff` names and the sprites that
+  break the rule are `pv_loading_ring0`, `pv_loading_light0`–`3`,
+  `px_bunk_line` — rings, glows, lights, thin lines. That the exceptions are all
+  effect-like artwork *without* the naming convention says more about the field
+  than the rule it broke did.

docs/re/REFUTED.md

@@ -505,3 +505,9 @@ neighbourhood, not just the line.
 * "the bit `0x02` marks a transient element" → **refuted.** `pteff03` and
   `pteff03a` carry the bit and run to `t=250`, ramping to `a=255` and holding.
   [`ui-paint-order-key.md`](structures/ui-paint-order-key.md)
+* "bit `0x02` set ⇒ the sprite's name contains `eff`" (the one-way reading that
+  survived the biconditional's refutation) → **mine, and refuted disc-wide the
+  next iteration.** True 10/10 on `GP_TITLE` build 4; over 14 709 sprites it
+  fails on **2 657 of 4 995** bit-set ones. `P(eff|set) = 0.468` against
+  `P(eff|clear) = 0.144` — an association, not an implication.
+  [`ui-paint-order-key.md`](structures/ui-paint-order-key.md)

docs/re/data/eff-bit-census.txt

@@ -0,0 +1,24 @@
+# tools/re-capture/eff_bit_census.py over dat/GP_*.pak -- 2026-08-29
+
+sprites with a resolvable preceding name: 14709
+  bit SET   & name has 'eff' : 2338
+  bit SET   & name lacks 'eff': 2657   <-- counterexamples to 'set => eff'
+  bit clear & name has 'eff' : 1399
+  bit clear & name lacks 'eff': 8315
+
+  P(name has 'eff' | bit set)   = 0.468
+  P(name has 'eff' | bit clear) = 0.144
+
+  counterexamples (bit set, no 'eff'):
+    ('GP_BUNK.pak', 'px_top_extra.t32', '00008832', '220x126')
+    ('GP_BUNK.pak', 'px_bunk_line.t32', '00008832', '663x27')
+    ('GP_BUNK.pak', 'px_top_extra.t32', '00008832', '220x126')
+    ('GP_BUNK.pak', 'px_bunk_line.t32', '00008832', '663x27')
+    ('GP_BUNK.pak', 'pv_loading_line.t32', '00000832', '181x101')
+    ('GP_BUNK.pak', 'pv_loading_ring0.t32', '00000832', '142x142')
+    ('GP_BUNK.pak', 'pv_loading_light0.t32', '00000832', '29x25')
+    ('GP_BUNK.pak', 'pv_loading_light1.t32', '00000832', '30x29')
+    ('GP_BUNK.pak', 'pv_loading_light2.t32', '00000832', '29x30')
+    ('GP_BUNK.pak', 'pv_loading_light3.t32', '00000832', '25x29')
+    ('GP_BUNK.pak', 'pv_loading_ring1.t32', '00000832', '72x72')
+    ('GP_BUNK.pak', 'pv_loading_line.t32', '00000832', '181x101')

docs/re/structures/ui-paint-order-key.md

@@ -528,7 +528,8 @@ evidence rather than on a guess between two same-sized sprites.
 
 | hypothesis | verdict |
 |---|---|
-| bit ⟺ the name contains `eff` | **refuted** — `ptlogo_back2eff` is an `eff` name with the bit clear. All 10 bit-set sprites *are* `eff` names, so the implication holds one way only |
+| bit ⟺ the name contains `eff` | **refuted** — `ptlogo_back2eff` is an `eff` name with the bit clear |
+| bit ⇒ the name contains `eff` (the surviving one-way reading) | **also refuted, disc-wide — see below.** It held 10/10 on build 4 and fails on **2 657 of 4 995** bit-set sprites across the disc |
 | bit ⟺ the element is transient (gone before the screen settles) | **refuted** — `pteff03`/`pteff03a` carry the bit and run to `t=250`, ramping to `a=255` and holding, i.e. they persist |
 
 ### 🟡 What the exception looks like up close
@@ -549,3 +550,35 @@ of one image at one size.
 So the bit tracks something that also distinguishes two versions of the same
 artwork, alongside a different layer key. ❔ **Still not diagnosed**, but the
 search space is smaller by two and the attribution underneath it is now sound.
+
+
+### 🔴 The one-way implication is refuted too — build 4 was a local pattern
+
+Having fixed the attribution, the surviving reading was *"bit set ⇒ the name
+contains `eff`"*, true 10/10 on `GP_TITLE` build 4. Checked disc-wide with
+[`tools/re-capture/eff_bit_census.py`](../../../tools/re-capture/eff_bit_census.py)
+([data](../data/eff-bit-census.txt)) over 14 709 sprites whose preceding name
+resolves:
+
+| | count |
+|---|---|
+| bit SET & name has `eff` | 2 338 |
+| **bit SET & name lacks `eff`** | **2 657** |
+| bit clear & name has `eff` | 1 399 |
+| bit clear & name lacks `eff` | 8 315 |
+
+`P(eff | set) = 0.468` against `P(eff | clear) = 0.144`. **The implication fails
+more often than it holds.** What survives is an *association* — the bit is 3.3×
+enriched for `eff` names — and one build's 10/10 was a local naming habit, not a
+rule.
+
+🟡 The counterexamples are the interesting part: `pv_loading_ring0`,
+`pv_loading_light0`–`3`, `pv_loading_line`, `px_bunk_line`, `px_top_extra` —
+rings, glows, lights and thin lines. **Effect-like artwork that does not carry
+the `eff` naming convention.** Consistent with the bit marking effect sprites by
+authoring intent rather than by name, which is a description, not a decode.
+
+⚠️ Name caveat: these names come from the string **immediately preceding** each
+`T8aD`, validated 17/18 on build 4 against the child order. The one mismatch is
+the known `pteff04.t32` → registered as `8AX` case, so this is the **element**
+(`opt `) name, not the sprite's registered name.