diff --git a/Game/project.godot b/Game/project.godot
index d3b7c93c..6304e3de 100644
--- a/Game/project.godot
+++ b/Game/project.godot
@@ -21,9 +21,6 @@ run/main_scene="uid://bcq14356s3e2i"
 config/features=PackedStringArray("4.7", "Forward Plus")
 config/icon="res://icon.svg"
 run/main_scene.training="res://scenes/training.tscn"
-# Dedicated exports select the server boot scene before the interactive menu
-# is loaded. This is the same project-setting feature override used above by
-# the training export.
 run/main_scene.dedicated_server="res://scenes/server_boot.tscn"
 
 [autoload]
@@ -59,22 +56,8 @@ NetDebugOverlay="*res://scripts/net_debug_overlay.gd"
 window/size/viewport_width=1920
 window/size/viewport_height=1080
 window/size/mode=2
-; Task 0.17c: kept fixed at "viewport" + 1080p rather than moved to
-; "disabled", deliberately. A player on a 1440p/4K display cannot render
-; native this way, and a 1080p player cannot render lower than 1080p through
-; window scaling alone — but task 0.17b's Viewport.scaling_3d_scale already
-; covers "render lower than the window" independently of stretch mode (it
-; scales the 3D viewport's own internal resolution before this blit, not the
-; window itself), and task 0.15b found an unexplained ~6% non-uniform width
-; scaling on this project's one tested (Mac/Retina) machine — see
-; multiplayer-todo.md §5.5.1 — that needs understanding before stretch mode
-; is touched, not blindly carried into a resolution-dependent change.
 window/stretch/mode="viewport"
 window/stretch/aspect="expand"
-; Task 0.17: default matches VideoSettings.gd's VsyncMode.ADAPTIVE default —
-; VideoSettings.apply_vsync() overwrites this at runtime via DisplayServer as
-; soon as the autoload initializes, so this is only what's in effect for the
-; brief pre-autoload window and if VideoSettings ever fails to load.
 window/vsync/vsync_mode=2
 
 [editor_plugins]
diff --git a/Game/scripts/server_boot.gd b/Game/scripts/server_boot.gd
index e17f093a..36881e20 100644
--- a/Game/scripts/server_boot.gd
+++ b/Game/scripts/server_boot.gd
@@ -9,6 +9,15 @@ extends Node
 #
 # Run: godot --headless --path Game res://scenes/server_boot.tscn -- --port=7777
 #
+# Dedicated *exports* reach this scene without the CLI argument above, via the
+# `run/main_scene.dedicated_server` feature override in project.godot — the same
+# project-setting mechanism the training export uses for training.tscn. That
+# override is deliberately uncommented in project.godot: Godot's ConfigFile
+# writer does not round-trip comments, and a `#` block directly above a setting
+# can be spliced into the setting's own line on rewrite, silently commenting it
+# out and sending dedicated builds to the interactive main menu instead of here.
+# `tests/cases/test_project_settings.gd` fails loudly if that ever happens.
+#
 # Deliberately does not spawn a match yet — that's Phase 2's networked_match
 # scene. This is just the process shell: listen, log, idle cheaply.
 
diff --git a/Game/scripts/video_settings.gd b/Game/scripts/video_settings.gd
index 39b8556d..56cc2658 100644
--- a/Game/scripts/video_settings.gd
+++ b/Game/scripts/video_settings.gd
@@ -8,6 +8,31 @@ extends Node
 # load) rather than overwriting them outright, so the per-arena bloom tuning
 # in arena_01/02/03.tscn survives underneath the user's preference.
 
+# The two display project settings this autoload sits on top of are documented
+# here rather than in project.godot, because Godot's ConfigFile writer does not
+# round-trip comments — it drops `;` blocks outright and can splice `#` blocks
+# into the following line, silently commenting the setting out. Anything in
+# project.godot that needs an explanation must therefore be explained from the
+# code that owns it. `tests/cases/test_project_settings.gd` guards the settings
+# themselves against exactly that corruption.
+#
+# `window/stretch/mode="viewport"` + 1080p (task 0.17c): kept fixed rather than
+# moved to "disabled", deliberately. A player on a 1440p/4K display cannot
+# render native this way, and a 1080p player cannot render lower than 1080p
+# through window scaling alone — but task 0.17b's Viewport.scaling_3d_scale
+# (resolution_scale below) already covers "render lower than the window"
+# independently of stretch mode, since it scales the 3D viewport's own internal
+# resolution before this blit rather than the window itself. Task 0.15b also
+# found an unexplained ~6% non-uniform width scaling on this project's one
+# tested (Mac/Retina) machine — see multiplayer-todo.md §5.5.1 — which needs
+# understanding before stretch mode is touched, not blindly carrying into a
+# resolution-dependent change.
+#
+# `window/vsync/vsync_mode=2` (task 0.17): matches VsyncMode.ADAPTIVE below.
+# apply_vsync() overwrites it at runtime via DisplayServer as soon as this
+# autoload initializes, so the project setting is only in effect for the brief
+# pre-autoload window, and as a fallback if VideoSettings ever fails to load.
+
 signal settings_changed  # Arenas re-apply preset-gated Environment/light state live.
 
 # MSAA_2X appended at the end, not inserted, so existing user://settings.cfg
diff --git a/Game/tests/cases/test_project_settings.gd b/Game/tests/cases/test_project_settings.gd
new file mode 100644
index 00000000..6016791e
--- /dev/null
+++ b/Game/tests/cases/test_project_settings.gd
@@ -0,0 +1,90 @@
+extends "res://tests/test_case.gd"
+
+# Guards the project settings that are load-bearing but easy to destroy
+# silently. Godot's ConfigFile writer does not round-trip comments in
+# project.godot: it drops `;` blocks outright, and a `#` block sitting directly
+# above a setting can be spliced onto that setting's own line on rewrite, which
+# comments the setting out. A dedicated build would then boot the interactive
+# main menu instead of the server, and nothing would fail until someone noticed
+# a server process rendering a menu.
+#
+# The explanations that used to live as comments beside these settings are now
+# in the code that owns them — server_boot.gd and video_settings.gd.
+#
+# The feature-override assertions read project.godot as TEXT rather than through
+# ProjectSettings. Godot resolves `key.<feature>` overrides at load time against
+# the running build's own feature tags and does not expose the suffixed key, so
+# get_setting("run/main_scene.dedicated_server") returns "" in a normal editor/
+# headless run even when the line is perfectly intact. Reading the file also
+# matches the actual threat, which is textual corruption of the file.
+
+
+func _project_godot_lines() -> PackedStringArray:
+	var file := FileAccess.open("res://project.godot", FileAccess.READ)
+	if file == null:
+		return PackedStringArray()
+	return file.get_as_text().split("\n")
+
+
+# True only if `key="value"` appears as a real, uncommented assignment. A line
+# that got spliced into a `#`/`;` comment is deliberately NOT a match — that is
+# precisely the corruption being guarded against.
+func _has_setting_line(key: String, value: String) -> bool:
+	var wanted := "%s=\"%s\"" % [key, value]
+	for raw_line in _project_godot_lines():
+		var line := raw_line.strip_edges()
+		if line.begins_with("#") or line.begins_with(";"):
+			continue
+		if line == wanted:
+			return true
+	return false
+
+
+func test_project_godot_is_readable() -> void:
+	# Everything below is vacuously true if the file could not be opened.
+	assert_true(not _project_godot_lines().is_empty(), "project.godot readable and non-empty")
+
+
+func test_dedicated_server_feature_override_is_set() -> void:
+	# Consumed by dedicated exports; see server_boot.gd.
+	assert_true(
+		_has_setting_line("run/main_scene.dedicated_server", "res://scenes/server_boot.tscn"),
+		"run/main_scene.dedicated_server present and uncommented"
+	)
+
+
+func test_training_feature_override_is_set() -> void:
+	assert_true(
+		_has_setting_line("run/main_scene.training", "res://scenes/training.tscn"),
+		"run/main_scene.training present and uncommented"
+	)
+
+
+func test_physics_engine_is_jolt() -> void:
+	# The whole flight model and every trained policy assume Jolt. Silently
+	# reverting to Godot Physics would change ship/ball behaviour under bots
+	# trained against Jolt, without any other test failing on its own.
+	var engine: String = ProjectSettings.get_setting("physics/3d/physics_engine", "")
+	assert_eq(engine, "Jolt Physics", "3D physics engine")
+
+
+func test_required_autoloads_are_registered() -> void:
+	# NetworkManager in particular is reached by name from many scripts; losing
+	# it from [autoload] fails only at the point of use, deep in a smoke test.
+	for autoload_name in ["GameSettings", "VideoSettings", "NetworkManager", "MatchNet", "MatchSim"]:
+		assert_true(
+			ProjectSettings.has_setting("autoload/" + autoload_name),
+			"autoload/%s registered" % autoload_name
+		)
+
+
+func test_test_hook_autoloads_are_not_shipped() -> void:
+	# main_menu_test_hooks / lobby_test_hooks are added to [autoload] by hand
+	# when running those scene-level smoke tests, and must be removed again —
+	# see CLAUDE.md. Shipping one registered would run test code in the real
+	# game, so fail here rather than discovering it in a build.
+	for hook_name in ["MainMenuTestHooks", "LobbyTestHooks", "NetworkedMatchTestHooks"]:
+		assert_true(
+			not ProjectSettings.has_setting("autoload/" + hook_name),
+			"test hook autoload/%s must not be registered" % hook_name
+		)