diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index a066f461..f92f3942 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -34,8 +34,10 @@ Full walkthrough: [profiling guide](https://abdess.github.io/retrobios/wiki/prof
 
 - `bios/Manufacturer/Console/filename` for canonical files
 - `bios/Manufacturer/Console/.variants/filename.sha1prefix` for alternate versions
-- Files >50 MB go in GitHub release assets (`large-files` release)
-- RPG Maker and ScummVM directories are excluded from deduplication
+- A file too large for git goes to the `large-files` GitHub release and its
+  path into `.gitignore`, the list that decides what is served from the release
+- Trees addressed by path are kept out of deduplication (`NODEDUP_DIRS` in
+  `scripts/dedup.py`)
 - Two paths differing only by case break clones on Windows and macOS,
   and `tests/test_no_case_collisions.py` enforces this
 
diff --git a/scripts/generate_readme.py b/scripts/generate_readme.py
index b090d9f5..f665ab3a 100644
--- a/scripts/generate_readme.py
+++ b/scripts/generate_readme.py
@@ -719,8 +719,10 @@ Full walkthrough: [profiling guide]({link("wiki/profiling")}).
 
 - `bios/Manufacturer/Console/filename` for canonical files
 - `bios/Manufacturer/Console/.variants/filename.sha1prefix` for alternate versions
-- Files >50 MB go in GitHub release assets (`large-files` release)
-- RPG Maker and ScummVM directories are excluded from deduplication
+- A file too large for git goes to the `large-files` GitHub release and its
+  path into `.gitignore`, the list that decides what is served from the release
+- Trees addressed by path are kept out of deduplication (`NODEDUP_DIRS` in
+  `scripts/dedup.py`)
 - Two paths differing only by case break clones on Windows and macOS,
   and `tests/test_no_case_collisions.py` enforces this
 
diff --git a/tests/test_audit_regressions.py b/tests/test_audit_regressions.py
index f85d1eb5..b979f3af 100644
--- a/tests/test_audit_regressions.py
+++ b/tests/test_audit_regressions.py
@@ -5456,5 +5456,32 @@ class AnUnknownTargetIsRefusedUnderAll(unittest.TestCase):
         self.assertIn("retroarch", kept)
 
 
+class DocsDescribeTheRegistriesTheyName(unittest.TestCase):
+    """The contributing guide said files over 50 MB are release assets and that
+    RPG Maker and ScummVM were the trees kept out of dedup. `.gitignore`
+    decides the first, four committed files exceed 50 MB, and NODEDUP_DIRS
+    holds eleven trees."""
+
+    SIZE_RULE = re.compile(r"(over|larger than|>)\s*50\s*MB[^\n]*(release|asset)", re.I)
+
+    def _texts(self):
+        paths = sorted((ROOT / "wiki").glob("*.md"))
+        paths += [ROOT / "scripts" / "generate_readme.py", ROOT / "CONTRIBUTING.md"]
+        return [(p, p.read_text(encoding="utf-8")) for p in paths]
+
+    def test_no_page_says_size_decides_a_release_asset(self):
+        offenders = [str(p.relative_to(ROOT)) for p, text in self._texts()
+                     if self.SIZE_RULE.search(text)]
+        self.assertEqual(offenders, [])
+
+    def test_the_dedup_list_is_named_whole_or_by_its_constant(self):
+        from dedup import NODEDUP_DIRS
+        tools = (ROOT / "wiki" / "tools.md").read_text(encoding="utf-8")
+        line = next(l for l in tools.splitlines() if "NODEDUP_DIRS" in l)
+        self.assertEqual(sorted(d for d in NODEDUP_DIRS if d not in line), [])
+        readme_gen = (ROOT / "scripts" / "generate_readme.py").read_text(encoding="utf-8")
+        self.assertIn("NODEDUP_DIRS", readme_gen)
+
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/wiki/architecture.md b/wiki/architecture.md
index ff62e513..c9efa1d4 100644
--- a/wiki/architecture.md
+++ b/wiki/architecture.md
@@ -241,7 +241,7 @@ platform's own verification mode.
 | `zippedFile` entries | MD5 is of the ROM inside the ZIP, not the ZIP itself |
 | Regional variants (same filename) | `by_path_suffix` index disambiguates |
 | MAME BIOS ZIPs | `contents` field documents inner structure |
-| RPG Maker/ScummVM | excluded from dedup (NODEDUP) to preserve directory structure |
+| Trees addressed by path (RPG Maker, ScummVM, tzdata, c64-emu and the rest of `NODEDUP_DIRS`) | excluded from dedup to keep files that are equal by design |
 | `strip_components` in data dirs | flattens cache prefix to match expected path |
 | case-insensitive dedup | prevents `font.rom` + `FONT.ROM` conflicts on Windows/macOS |
 | frozen snapshot cores | `.info` may reflect current version while code is pinned to an old one. Only the frozen source at the pinned tag is reliable (e.g. desmume2015, mame2003) |
diff --git a/wiki/profiling.md b/wiki/profiling.md
index a1c91de5..10106dbf 100644
--- a/wiki/profiling.md
+++ b/wiki/profiling.md
@@ -411,7 +411,7 @@ partitions), and `game_count`.
 | `description` | what this file is |
 | `note` | additional context |
 | `contents` | structure of files inside a BIOS ZIP (`name`, `description`, `size`, `crc32`) |
-| `storage` | `embedded` (default), `external`, `user_provided`, or `large_file`/`release` for files > 50 MB stored as release assets |
+| `storage` | `embedded` (default), `external`, `user_provided`, or `large_file`/`release` for files stored as release assets (listed in `.gitignore`) |
 | `agnostic` | true if any file under the system path within size constraints satisfies the requirement |
 | `unsourceable` | reason why the file cannot be sourced (acknowledged gap) |
 | `destination` | target path within the BIOS directory |
diff --git a/wiki/release-process.md b/wiki/release-process.md
index 9be05d9e..865b7d0c 100644
--- a/wiki/release-process.md
+++ b/wiki/release-process.md
@@ -124,8 +124,10 @@ merge, and again on the commit a direct push puts at the head of main.
 
 ## Large files management
 
-Files larger than 50 MB are stored as assets on a permanent GitHub release
-named `large-files` (to keep the git repository lightweight).
+Files too large for git are stored as assets on a permanent GitHub release
+named `large-files`. Size does not decide it: four committed files are over
+50 MB (`history.xml`, `default-GM.sf3`, `5.avi`, `tbblue.mmc`) and are served
+from the repository like any other.
 
 Examples: PS3UPDAT.PUP, PSVUPDAT.PUP, PSP2UPDAT.PUP, the DSi NAND images,
 maclc3.zip, Firmware.19.0.0.zip (Switch), the QEMU EDK2 firmware, the ScummVM
diff --git a/wiki/tools.md b/wiki/tools.md
index 79e923f6..6adb1ffd 100644
--- a/wiki/tools.md
+++ b/wiki/tools.md
@@ -709,8 +709,10 @@ at. Writing is explicit: the pipeline only ever reports.
 
 ## Large files
 
-Files over 50 MB are stored as assets on the `large-files` GitHub release.
-They are listed in `.gitignore` to keep the git repository lightweight.
+Files too large for git are stored as assets on the `large-files` GitHub
+release. `.gitignore` is the list of them: a `bios/` path listed there is a
+release asset, whatever its size, and a committed file is served from the
+repository even past 50 MB.
 `generate_db.py` downloads them from the release when rebuilding the database,
 using `fetch_large_file()` from `common.py`. The same function is used by
 `generate_pack.py` when a file has a hash mismatch with the local variant.
diff --git a/wiki/troubleshooting.md b/wiki/troubleshooting.md
index ed7fcb0a..493b3191 100644
--- a/wiki/troubleshooting.md
+++ b/wiki/troubleshooting.md
@@ -154,7 +154,7 @@ in [verification modes](verification-modes.md#severity-matrix).
 Focus on CRITICAL issues first. WARNING files improve the experience but aren't
 strictly necessary. INFO files are nice to have.
 
-**Large files (over 50 MB):**
+**Large files (release assets):**
 
 Files like PS3UPDAT.PUP, PSVUPDAT.PUP, and Switch firmware are too large for the
 git repository. They are stored as GitHub release assets under the `large-files`