re: the (16,32] gate is != 16 && <= 32, a validity check on a load parameter

Corrects this corpus's own notation: there is no lower bound, values
below 16 pass.

sub_8225EC78(X, kind, ...) -- the function carrying "script load
cancel" -- stores its second argument into X+12 and applies the same
two tests to it immediately, bailing out of the load.  So the gate is
the object's invariant, re-checked at every later touch, not a
selector.  42 sites image-wide have the shape, 34 of them in one code
region plus 3 in sub_8225EC78.

Object chain: X = [GamePart+104] is the current script instance
(installed at 0x821A78EC, previous one torn down via sub_8225EB60);
X+4 -> Y; Y+4 -> the ScriptPhase; Y+72 and [ScriptPhase+10152] get
the answer.

Refutes my own lead in the same pass: "X+12 is a GamePart id and 16 is
the unregistered one" fails its control -- 1, 2 and 18 are also absent
from the RegisterToFactory list, so 16 is one of four gaps.

Docs only; artefacts byte-identical.

docs/re/BACKLOG.md

@@ -450,6 +450,34 @@ unknown, what evidence exists, and what the first step would be. Move an item in
   System 15, MainGame 17, PauseMenu 19, StageClear 20, MissionLog 21, GameOver 22,
   Debriefing 23, Dialog 24, Tutorial 25, ChallengeMission 26, Leaderboard 27.
 
+* ✅🔴 **(2026-08-27) THE `(16,32]` GATE IS READ — it is `!= 16 && <= 32`, a
+  VALIDITY CHECK on a load-time parameter, and my own GamePart-id lead is killed
+  by its control. [structures/isl-condition-builtins](structures/isl-condition-builtins.md).**
+  🔴 **The corpus's own notation was wrong.** `(16, 32]` implies a lower bound;
+  there is none — everything **below 16 passes**. The test is
+  `kind != 16 && kind <= 32`.
+  ✅ **`X+12` is a constructor argument, not engine state.** `sub_8225EC78(X,
+  kind, …)` — the function carrying `"script load cancel"` — does
+  `stw r4, 12(r30)` and then applies **those same two tests to `r4`**, bailing
+  out of the load. Every later site re-tests the field it just stored, so the
+  gate is the object's **invariant**, not a selector between behaviours. Control:
+  **42 sites image-wide** have this exact `cmpi 16` → `cmpi 32` shape, **34 in one
+  region** (`sub_821A9DC8`, `sub_821AA1B0`, `sub_821AB570`, `sub_821AB650`) plus 3
+  in `sub_8225EC78` — one object, guarded everywhere it is touched.
+  ✅ **The object chain is read.** `X` is installed at `0x821A78EC`
+  (`stw r25, 104(r30)`), the previous instance torn down first via
+  `sub_8225EB60` — so **`X = [GamePart+104]` is the game part's CURRENT SCRIPT
+  INSTANCE**. `X+4` → `Y`; `Y+4` → the **ScriptPhase**; `Y+72` = the answer, and
+  `[ScriptPhase+10152]` gets the same value. `X+12` arrives as `[r21+8]`, `r21`
+  being `sub_821A6CF0`'s second argument.
+  🔴 **REFUTED, my own lead, in the same pass.** GamePart ids run 0…27 and **16 is
+  not among them**, which made "`X+12` is a GamePart id, 16 being the unregistered
+  one" very inviting. Its control kills it: **1, 2 and 18 are also missing** from
+  the `RegisterToFactory` list, so 16 is one of *four* gaps, not a unique one.
+  Not adopted.
+  🟡 Not settled: what the kind **means**. The gate is read; the value's domain is
+  not, and chasing it needs another hop up (`sub_821A6CF0`'s caller).
+
 ## ✅✅ SOLVED — the mission freeze was a modal sign-in dialog (2026-08-26)
 
 `XamShowSigninUI` opens a modal dialog and `xeXamDispatchDialog` blocks the

docs/re/structures/isl-condition-builtins.md

@@ -134,6 +134,49 @@ left unnamed rather than named off an unverified premise.
 and exactly one reference in the image — a tail `b` from `0x821AC064` — so the
 string recipe finds nothing there.
 
+## 🔴✅ (2026-08-27) The gate is `!= 16 && <= 32` — and it is a VALIDITY CHECK, not a selector
+
+🔴 **First, a correction to this page's own notation.** Written as `(16, 32]` it
+implies a lower bound. There is none:
+
+```
+8225EC90  cmpi cr6, 0, r4, 16
+8225EC94  stw  r4, 12(r30)          ; <- the field IS the argument
+8225EC98  bc   12, eq, <bail>       ; == 16 -> bail
+8225EC9C  cmpi cr6, 0, r4, 32
+8225ECA0  bc   12, gt, <bail>       ; >  32 -> bail
+```
+
+Everything **below** 16 passes. The condition is `kind != 16 && kind <= 32`.
+
+✅ **`X+12` is a constructor parameter, not engine state.** `sub_8225EC78(X,
+kind, …)` — the function carrying the string `"script load cancel\n"` — stores
+its second argument into `+12` and applies the identical pair of tests to it
+immediately, bailing out of the load. Every later occurrence re-tests the field
+it just stored. So the gate is that object's **invariant**, re-checked wherever
+it is touched, not a switch selecting between behaviours.
+
+✅ **Where it is checked**: 42 sites image-wide with this exact `cmpi 16` →
+`cmpi 32` shape, **34 of them in one code region** — `sub_821A9DC8`,
+`sub_821AA1B0`, `sub_821AB570`, `sub_821AB650` — plus 3 in `sub_8225EC78`. One
+object, guarded everywhere.
+
+✅ **And the object chain is now read.** `X` is installed at `0x821A78EC`
+(`stw r25, 104(r30)`), the previous one torn down first through `sub_8225EB60`;
+so `X = [GamePart+104]` is **the game part's current script instance**. From
+there `X+4` → `Y`, and `Y+4` → the **ScriptPhase**, `Y+72` = the answer, with
+`[ScriptPhase+10152]` receiving the same value. `X+12`'s value arrives as
+`[r21+8]`, `r21` being `sub_821A6CF0`'s own second argument.
+
+🔴 **A tempting reading, killed by its control.** GamePart ids (from the
+`RegisterToFactory<N,…>` strings) run 0…27, and **16 is not among them** — which
+makes "`X+12` is a GamePart id and 16 is the unregistered one" very inviting.
+It fails: **1, 2 and 18 are also absent** from that list, so 16 is one of *four*
+gaps, not a unique one. Nothing distinguishes it. The reading is not adopted.
+
+🟡 So what the kind **means** is still open — the gate is now read, but the
+value's domain is not.
+
 🟡 Its neighbours belong to the same cluster: `builtin103` reads
 `[phase+10156]` and `[phase+10152]` (9 and 7 writers), and a sibling vtable stub
 clears `[phase+10152]`. The shape is an engine→script status trio, but that is a