re: making turrets targets does not save the escort — the effect is inside the noise

The Stage-02 outcome write-up ended by naming "turrets near the asset must
become targets" as the fix worth ~50% of the escort damage. That was an
inference from a co-presence attribution, not a measurement. Run it and it
does not hold.

Also corrects the run labelling: pilot.py gained the SYLPH_KILL_TURRETS gate
two minutes before mission02 started, so mission02 was already a treatment run,
not a second baseline. Only mission01 (0 of 3968 pilot frames targeting a
turret) is the baseline.

At a common t=428s: baseline 46.9% escort hull, treatment 44.5% and 53.0%. The
two runs of the same arm differ by more than either differs from the baseline,
and the escort still reaches zero at t~590-670s in all three. So the
transferable finding is the power limit: one 430s flight cannot resolve an
effect below ~9 percentage points, and every single-run pilot conclusion,
including this one's, is inside it.

What does reproduce: the assault is scripted (onset 166/167/166s), and the
e007/e010 damage split is 50/50 in all three arms including the one that never
fires at a turret -- so that attribution measures the wave script, not us.

Also records that the viewer's include_external hypothesis in BACKLOG is dead
(it defaults true and is threaded through unchanged).

docs/re/BACKLOG.md

@@ -58,3 +58,26 @@ class cannot hide behind `e106` passing.
 handedness, node-instance recursion) is not re-breaking a correct assembly — compare
 the viewer's placement against `assemble_ship`'s output directly before blaming the
 format layer.
+
+---
+
+## Viewer: `include_external` is already on — that hypothesis is dead
+
+**Checked 2026-08-11.** The item above names "first that it passes
+`include_external = true` (`iso_loader.rs:4012`)" as the cheap first step. It
+does: `ShipBrowser::show_external` defaults to `true`
+(`iso_loader.rs:643`), the checkbox reads it (`ui.rs:1593`) and it is threaded
+through `RequestShipRender` → `build_ship_model` → `assemble_ship` unchanged
+(`ui.rs:1689`, `iso_loader.rs:4012`). So a ship rendered by the viewer is the
+full external assembly, not the bare hull.
+
+The viewer also does not have a transform stack of its own to blame: it bakes
+`ScenePart::apply` straight into the vertices and rotates normals by the same
+`p.m` (`iso_loader.rs:4030-4062`), so its placement is `assemble_ship`'s output
+by construction. What remains unexcluded, in order of cheapness: the mirror
+handling (`det < 0` reverses triangle winding only — a reflected part keeps its
+reflected geometry), `Xbg7Model::models_named` resolving the wrong sub-model when
+a resource name repeats, and the exhaust cones. **Next step is a visual**: the
+diagnosis has run out of things it can settle by reading, so the viewer needs to
+be run against a known-good class (`e106`) and its render compared with
+`ship_render`'s.

docs/re/captures/escort-decay-ab.csv

@@ -0,0 +1,161 @@
+run,turret_rule,t_s,acropolis_hull,e007_alive,e007_killed_cum
+mission01,off,0,25000.0,0,0
+mission01,off,10,25000.0,5,0
+mission01,off,20,25000.0,6,0
+mission01,off,30,25000.0,6,0
+mission01,off,40,25000.0,6,0
+mission01,off,50,25000.0,8,0
+mission01,off,60,25000.0,11,0
+mission01,off,70,25000.0,11,3
+mission01,off,80,25000.0,8,3
+mission01,off,90,25000.0,8,3
+mission01,off,100,25000.0,10,3
+mission01,off,110,25000.0,14,3
+mission01,off,120,25000.0,16,3
+mission01,off,130,25000.0,17,3
+mission01,off,140,25000.0,20,3
+mission01,off,150,25000.0,23,3
+mission01,off,160,25000.0,26,4
+mission01,off,170,24509.5,33,4
+mission01,off,180,24509.5,37,4
+mission01,off,190,24419.5,38,5
+mission01,off,200,24212.5,41,5
+mission01,off,210,23447.5,40,5
+mission01,off,220,23447.5,40,5
+mission01,off,220,23447.5,40,5
+mission01,off,230,23447.5,41,5
+mission01,off,230,23447.5,41,5
+mission01,off,240,22912.0,43,5
+mission01,off,240,22867.0,43,5
+mission01,off,250,22667.0,42,6
+mission01,off,250,22647.0,42,6
+mission01,off,260,22334.5,44,6
+mission01,off,260,22177.9,44,6
+mission01,off,270,21101.2,46,6
+mission01,off,270,21101.2,45,6
+mission01,off,280,20292.6,46,6
+mission01,off,280,20279.1,46,6
+mission01,off,290,19598.5,58,6
+mission01,off,290,19598.5,58,6
+mission01,off,300,18725.2,58,6
+mission01,off,300,18658.5,47,6
+mission01,off,310,18231.9,47,6
+mission01,off,310,18231.9,47,6
+mission01,off,320,17425.2,47,6
+mission01,off,330,17046.9,49,6
+mission01,off,340,16044.8,49,7
+mission01,off,350,15461.5,50,7
+mission01,off,360,14956.3,51,7
+mission01,off,370,14425.5,51,8
+mission01,off,380,13910.5,51,8
+mission01,off,390,13418.9,49,11
+mission01,off,400,13218.9,45,12
+mission01,off,410,12517.9,44,12
+mission01,off,420,12161.3,44,13
+mission01,off,430,11601.3,44,13
+mission02,on,0,25000.0,0,0
+mission02,on,10,25000.0,5,0
+mission02,on,20,25000.0,6,0
+mission02,on,30,25000.0,5,0
+mission02,on,40,25000.0,5,1
+mission02,on,50,25000.0,7,1
+mission02,on,60,25000.0,10,1
+mission02,on,70,25000.0,7,4
+mission02,on,80,25000.0,7,4
+mission02,on,90,25000.0,7,4
+mission02,on,100,25000.0,7,4
+mission02,on,110,25000.0,9,4
+mission02,on,120,25000.0,14,4
+mission02,on,130,25000.0,16,4
+mission02,on,140,25000.0,19,4
+mission02,on,150,25000.0,19,4
+mission02,on,160,25000.0,23,5
+mission02,on,170,24730.0,28,5
+mission02,on,180,24730.0,32,5
+mission02,on,190,24730.0,36,5
+mission02,on,200,24640.0,43,6
+mission02,on,210,24190.0,46,6
+mission02,on,220,24055.0,47,6
+mission02,on,220,24055.0,47,6
+mission02,on,230,24055.0,49,6
+mission02,on,230,24055.0,49,6
+mission02,on,240,23474.5,52,6
+mission02,on,240,23474.5,52,6
+mission02,on,250,23474.5,53,6
+mission02,on,250,23474.5,53,6
+mission02,on,260,23474.5,54,6
+mission02,on,260,23474.5,54,6
+mission02,on,270,22697.0,54,6
+mission02,on,270,22697.0,54,6
+mission02,on,280,22091.2,56,6
+mission02,on,280,22091.2,55,7
+mission02,on,290,21577.9,55,7
+mission02,on,290,21555.4,55,7
+mission02,on,300,20799.1,56,7
+mission02,on,310,19781.1,55,7
+mission02,on,320,18925.8,56,8
+mission02,on,330,18592.5,56,8
+mission02,on,340,17432.5,57,8
+mission02,on,350,16932.6,59,8
+mission02,on,360,16171.6,58,9
+mission02,on,370,15017.6,58,11
+mission02,on,380,14217.2,59,11
+mission02,on,390,13322.2,59,12
+mission02,on,400,12808.9,58,13
+mission02,on,410,12090.6,61,16
+mission02,on,420,11440.6,66,19
+mission02,on,430,11127.3,55,19
+mission03,on,0,25000.0,0,0
+mission03,on,10,25000.0,3,0
+mission03,on,20,25000.0,8,0
+mission03,on,30,25000.0,5,0
+mission03,on,40,25000.0,6,0
+mission03,on,50,25000.0,8,0
+mission03,on,60,25000.0,9,0
+mission03,on,70,25000.0,16,0
+mission03,on,80,25000.0,10,0
+mission03,on,90,25000.0,11,0
+mission03,on,100,25000.0,10,2
+mission03,on,110,25000.0,15,2
+mission03,on,120,25000.0,12,2
+mission03,on,130,25000.0,10,4
+mission03,on,140,25000.0,11,6
+mission03,on,150,25000.0,14,6
+mission03,on,160,25000.0,17,7
+mission03,on,170,24685.0,24,7
+mission03,on,180,24640.0,23,7
+mission03,on,190,24640.0,27,7
+mission03,on,200,24460.0,26,8
+mission03,on,210,24100.0,28,8
+mission03,on,220,24100.0,29,9
+mission03,on,230,24100.0,28,11
+mission03,on,230,24100.0,28,11
+mission03,on,240,23810.0,35,11
+mission03,on,240,23810.0,36,11
+mission03,on,250,23630.0,36,12
+mission03,on,250,23630.0,36,12
+mission03,on,260,23630.0,38,13
+mission03,on,260,23630.0,38,13
+mission03,on,270,22998.0,39,13
+mission03,on,270,22908.0,39,13
+mission03,on,280,22197.5,40,13
+mission03,on,280,22188.5,40,13
+mission03,on,290,21602.4,38,13
+mission03,on,290,21602.4,38,13
+mission03,on,300,21042.4,39,13
+mission03,on,300,20975.8,39,13
+mission03,on,310,20529.1,41,15
+mission03,on,310,20529.1,41,15
+mission03,on,320,19812.5,38,17
+mission03,on,320,19767.5,38,17
+mission03,on,330,19434.2,39,18
+mission03,on,340,18785.9,37,19
+mission03,on,350,18339.2,37,19
+mission03,on,360,17528.1,38,19
+mission03,on,370,16901.5,37,19
+mission03,on,380,16260.7,35,19
+mission03,on,390,15708.2,37,19
+mission03,on,400,15346.2,37,19
+mission03,on,410,14412.1,36,20
+mission03,on,420,13951.9,37,22
+mission03,on,430,13211.9,35,23

docs/re/mission-outcome-stage02.md

@@ -66,6 +66,8 @@ the mission scores **objectives** and **the escort**, and the fighter population
 moment the escort passes 33 % is not a good run — it is **unspent risk budget**.
 
 Concretely, for the next attempt, in priority order:
+(**Step 1 below was run on 2026-08-11 and did not hold — see the follow-up A/B at
+the end of this file before acting on it.**)
 
 1. **Turrets near the asset must become targets**, not keep-out zones — accepting
    hull damage is the only way to cut ~50 % of the incoming escort damage. The
@@ -87,3 +89,93 @@ one-blocking-foreground-call rule still stands, which caps a single attempt at
 the tool's 600 s timeout. And do not pipe a long run through `tail` — the first
 attempt printed nothing because `timeout` killed the pipeline before it flushed;
 the on-disk artifacts are what survived.
+
+---
+
+# Follow-up A/B (2026-08-11): making turrets targets does **not** save the escort
+
+**Status: ✅ measured (3 runs), and it falsifies the causal claim above.** The
+section above ends by naming step 1 — "turrets near the asset must become
+targets" — as the fix worth ~50 % of the escort damage. That was an *inference
+from an attribution*, never a measurement. It has now been run, and it does not
+hold.
+
+## First, a correction to the run labelling
+
+`pilot.py` gained the `SYLPH_KILL_TURRETS` gate at 21:20:28 on 2026-08-10;
+`/sylph-home/re/mission02` started at **21:22:25**, i.e. *after* it, with the
+gate **on**. So `mission02` was never a second baseline — it is a treatment run
+that the previous session produced but never reported. The arms are:
+
+| run | turret rule | evidence (`pilot.log`) |
+|---|---|---|
+| `mission01` | **off** (baseline) | `tgt=e007` on **0** of 3968 lines |
+| `mission02` | **on** | `tgt=e007` on 1588 of 3844 lines |
+| `mission03` | **on** (this session) | `tgt=e007` on 1218 of 3514 lines |
+
+`mission01` predates the edit, so the *only* difference between the arms is the
+gate. Everything else — build, save slot, nav route, loadout — is identical.
+
+## The result, all three runs truncated to a common t = 428 s
+
+| run | rule | ACROPOLIS @428 s | % | decay rate | turrets seen | turrets killed | attack onset |
+|---|---|---|---|---|---|---|---|
+| `mission01` | off | 11735 | 46.9 % | 50.3 HP/s | 92 | 30 | 166 s |
+| `mission02` | on | 11127 | 44.5 % | 52.7 HP/s | 98 | 34 | 167 s |
+| `mission03` | on | 13257 | 53.0 % | 44.4 HP/s | 88 | 41 | 166 s |
+
+**The two runs of the *same* arm differ by 8.5 percentage points (2130 HP) —
+more than either differs from the baseline.** The baseline sits *between* the two
+treatment runs on escort hull and on decay rate. So the effect of the turret rule
+is **not resolvable at n=1 per arm**, and the honest statement is: it was not
+demonstrated. Extrapolating each run's own rate, the escort still reaches zero at
+**t ≈ 590–670 s** in every arm — the mission is lost in all three.
+
+The rule does do the mechanical thing it was written to do (turret kills 30 → 34,
+41; 1218–1588 frames spent with a turret as the committed target). It just does
+not convert into escort hull.
+
+![Stage 02 at t≈430 s with the turret rule on — WARSHIPS 0000, REMAINING OB 008](captures/mission03-turretrule-t430.png)
+
+## What *is* reproducible across all three runs
+
+These are the numbers to build on, because they repeat to within a percent:
+
+- **The assault on the ACROPOLIS is scripted, not emergent.** Onset at
+  **166 / 167 / 166 s** — ±1 s across three runs with completely different pilot
+  behaviour in between. Nothing the pilot does moves it.
+- **The damage split is a property of the scenario, not of our targeting.**
+  `e007` turrets vs `e010` bombers is **50.6/49.4, 50.0/50.0, 51.0/49.0** — and
+  the baseline, in which we never fired at a turret at all, splits the same way.
+  A co-presence attribution that is invariant to whether we attack one of the two
+  classes is measuring the wave script, not our contribution.
+- **Turrets die anyway**: 30 of 92 are already dead by t=428 s in the baseline,
+  from friendly fire. The turret rule adds ~4–11 kills on top of that, which is
+  why its escort-hull effect is small enough to be buried in run-to-run noise.
+- `WARSHIPS 0000` and `REMAINING OB` rising (004 → 008) in **every** run,
+  including this one.
+
+Per-run series: [`captures/escort-decay-ab.csv`](captures/escort-decay-ab.csv)
+(10 s grid, hull + turret alive/killed counts for all three runs).
+
+## The methodological finding, which is the transferable one
+
+**A single 430 s flight cannot resolve an escort-hull effect smaller than ~9
+percentage points.** Every pilot conclusion drawn from one run — including step 1
+above, and including anything drawn from `mission03` alone — is inside the noise.
+Each run costs ~10 minutes of wall clock and one blocking foreground call, so a
+properly powered A/B is ~6 runs ≈ 1 hour. **Any future pilot tuning must budget
+that, or not be believed.**
+
+## What this means for the reason we wanted a win
+
+Story progress was wanted only because unit definitions instantiate per stage, so
+unit-field coverage is stuck at 21/110 ([unit struct](structures/unit-struct-runtime.md)).
+This result says the pilot route to that coverage is expensive and unproven: the
+escort dies on a script at ~10–11 minutes, our best lever moved it by less than
+the noise, and the objective class (`WARSHIPS`) has never been touched in any run
+ever. **Before spending another hour on pilot tuning, the cheaper lever to price
+is the save file** — if the profile's save data can be read and understood, stage
+unlock state is a much shorter path to the same coverage, and the save format is
+itself something the reimplementation needs. Marked `NEEDS-HUMAN` as a direction
+choice; no save-file modification has been attempted.