diff --git a/docs/re/data/voice-three-streams-runtime.txt b/docs/re/data/voice-three-streams-runtime.txt
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+w> 01000014 XMA-PROBE active (ctx 0 first decode) — cvar parsed OK
+w> 01000014 XMA-PARAM ctx=0 buf=0 ptr=0x13544000 read_off=32 stereo=1 channels=2 rate_id=3 rate=48000 packets=632 byte_size=1294336 sig_off=1024 head=080000000095fc01c001020408c01f7f0004081023007dfc001020408c01f7f0 sig=004081023007dfc001020408c01f7f0004081023007dfc001020408c01f7f0004081023007dfc001020408c01f7f0004
+w> 01000014 XMA-PARAM ctx=1 buf=0 ptr=0x13682000 read_off=32 stereo=1 channels=2 rate_id=3 rate=48000 packets=546 byte_size=1118208 sig_off=1024 head=080000000095fc01c001020408c01f7f0004081023007dfc001020408c01f7f0 sig=004081023007dfc001020408c01f7f0004081023007dfc001020408c01f7f0004081023007dfc001020408c01f7f0004
+w> 01000014 XMA-PARAM ctx=2 buf=0 ptr=0x13795000 read_off=32 stereo=1 channels=2 rate_id=3 rate=48000 packets=572 byte_size=1171456 sig_off=1024 head=080000000095fc01c001020408c01f7f0004081023007dfc001020408c01f7f0 sig=004081023007dfc001020408c01f7f0004081023007dfc001020408c01f7f0004081023007dfc001020408c01f7f0004
diff --git a/docs/re/structures/voice-three-streams-are-concurrent.md b/docs/re/structures/voice-three-streams-are-concurrent.md
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+# 🔴 A voice cue's three streams are DECODED TOGETHER — they are not alternative presentations
+
+**Classification: measured.** Xenia Canary, `--xma_param_probe=true`, one boot
+into the intro movie, 2026-08-29. Log excerpt committed at
+[`data/voice-three-streams-runtime.txt`](../data/voice-three-streams-runtime.txt).
+
+**This refutes a framing of mine that two documents and the port's exporter were
+built on**, so it is written as its own page rather than as an edit.
+
+## What was believed
+
+[`voice-region-leading-chunk.md`](voice-region-leading-chunk.md) established that
+a long voice cue's byte span holds **three** streams, and read them as *three
+presentations of one take* — a defensible reading of the evidence then available
+(they are the same duration, and their content correlates strongly). From it came
+the instruction **"take one stream, do not sum"**, which the port implemented.
+
+The open question was *which* presentation the game plays.
+
+## What the game does
+
+The question has no answer, because the premise is wrong. Canary's
+`xma_param_probe` — a cvar whose own comment says it is keyed so as to reveal
+"**WHICH sub-wave of a movie's `.slb` the game actually decodes**" — shows the
+guest opening **three XMA contexts and decoding all three concurrently**:
+
+| context | packets | `byte_size` | channels | rate | disc stream |
+|---|---|---|---|---|---|
+| **0** | 632 | **1 294 336** | 2 | 48 000 | `ADV` stream 1 (RIFF 1 294 396 − 60) |
+| **1** | 546 | **1 118 208** | 2 | 48 000 | `ADV` stream 2 (1 118 268 − 60) |
+| **2** | 572 | **1 171 456** | 2 | 48 000 | `ADV` stream 3 (1 171 516 − 60) |
+
+**Three-way, byte-exact**, against sizes taken independently off the disc. Only
+these three contexts appear in the run.
+
+So the three streams are **simultaneous**, not alternative. A consumer that picks
+one is discarding two thirds of what the game mixes.
+
+## 🟡 The obvious reading is 5.1, and it is NOT established
+
+Three concurrent **stereo** streams is six channels, and N stereo streams is
+exactly how XMA carries multichannel audio on the 360. It would explain a lot at
+once:
+
+* the differing declared byte rates — different channel pairs, different content,
+  same encoder quality;
+* the port's content measurements, which become measurements *of channels*:
+  `ADV` stream 2 is **mono-in-stereo** (one channel digitally silent — a centre
+  paired with a silent LFE looks exactly like that), stream 3 is **dual-mono**
+  (a centre-panned line in an L/R pair is L = R exactly), and `S00A`'s third
+  stream is **digital silence** (surrounds, on a dialogue-only cue);
+* stream 3 measuring **0.60 ×** stream 2 with the residual 26.8 dB down — which
+  is what a correlated channel pair at a lower level looks like, and *not* only
+  what a duplicate looks like;
+* ✅ and the census dichotomy already on record: inter-descriptor spans hold
+  **1 stream or 3, never 2** (258 and 28). If 3-stream is 5.1 and 1-stream is
+  mono/stereo, the missing 2 is the missing 4-channel configuration.
+
+⚠️ **Against it**, and the reason this stays 🟡: all three `fmt ` chunks declare
+`ChannelMask = 0x0002` **identically**, which is not what distinct channel roles
+should look like. Either the mask is unset on this disc or the offset is
+mis-taken; it is weak evidence either way, and no channel-role assignment is
+claimed here.
+
+❔ **Which stream is which channel pair is unknown.** Nothing measured here
+assigns roles, and the port must not infer them from stream order.
+
+## 🔴 What this withdraws
+
+* **"Three presentations of one take"** — withdrawn. Three concurrent streams of
+  one take.
+* **"Take one stream, do not sum"** — withdrawn. It was my instruction, the port
+  implemented it, and it discards two of three decoded streams.
+  ⚠️ **This does not make the previous behaviour right either.** An equal-gain
+  `1/n` sum of channel pairs is not a downmix, and the port's measured 6.02 dB
+  loss from summing a silent stream was real. The correct handling needs the
+  channel roles, which are open. **Neither "pick one" nor "sum at 1/n" is
+  established; a consumer is authoring, and should say so.**
+* **"Which presentation does the game play?"** — dissolved rather than answered.
+
+✅ **What survives untouched:** every content measurement the port made, and the
+byte-level structure in
+[`voice-region-leading-chunk.md`](voice-region-leading-chunk.md) — the leading
+chunk being stream 1 clipped by our own 1.5 MB guard, the 70 + 8 + 17
+decomposition, the bank-header discriminator. Those are about bytes and they did
+not depend on the framing.
+
+## Reach
+
+* **One cue, one boot.** `ADV` only. That 28 cues on the disc are 3-stream is
+  decoded from the bytes, but that all 28 decode concurrently is measured on
+  **one** of them.
+* The probe fires on **first decode** per `(buffer ptr, packet count)`, so this
+  shows all three being *started*; it does not by itself prove they play to the
+  end in lockstep. Their equal durations and the port's sample-synchronous
+  correlation both point that way.
+* Nothing here identifies the **mix** the guest applies downstream of the three
+  decoders.