port: correcting my own correction -- none of the 1530 is a question without content

I told the Decoder their denominator held 1530 questions that were never asked:
records with no timed keyframe, where 'does +0x08 equal the largest keyframe time'
has no meaning. I did not check that and it is wrong.

Of the 1530 excluded, ZERO have no timed keyframe at all and all 1530 are timed
with every pose at t=0. Every one has a largest keyframe time; it is 0. So the
question is well-formed there and the answer is 'not exact', because a static
record still declares a cycle length and a nonzero +0x08 against a largest time of
0 is a real disagreement rather than an absent one.

That makes their 49.6% defensible rather than mistaken. Two statistics over two
populations: 92.3% of records whose largest keyframe time is > 0, and 49.6% of all
nested records including static ones. Neither is the corrected version of the
other. I framed mine as correct and theirs as an artefact; the truthful statement
is that they answer different questions and both need their population attached --
which was my own point one message earlier, applied to their number and not to my
reading of it.

Their cause diagnosis is still right about the mechanism, max() returning Some(0)
rather than None, but 'records with no timed keyframe' describes zero records on
this disc. The mechanism is real and the population they attributed it to does not
exist.

Third-order and worth naming: they corrected an argument, I corrected their
denominator, and this corrects my characterisation of what was in it. Each step
was checkable in one scan, and each of us stated the interpretation confidently
while only the number had been measured. The numbers have agreed throughout; every
disagreement has been about what they were counting.

What survives untouched, and is the only part the port depends on: +0x08 equals
the largest keyframe time exactly where that time is nonzero, +0x04 does so 0% of
the time under either denominator, and the offset identification stands on both
scans.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF

docs/port/DECISIONS.md

@@ -9,7 +9,7 @@ dies, which is what this file is for.
 
 <!-- INDEX: generated by tools/port/index-decisions -- do not hand-edit -->
 
-309 sections. Search this before re-deriving anything.
+310 sections. Search this before re-deriving anything.
 
 * [P0 — the exporter, 2026-08-28](#p0--the-exporter-2026-08-28)
 * [P1 — Godot draws the screen, 2026-08-28](#p1--godot-draws-the-screen-2026-08-28)
@@ -320,6 +320,7 @@ dies, which is what this file is for.
 * [🔴 Their record layout was wrong and I had copied it — fourth relayed aside](#their-record-layout-was-wrong-and-i-had-copied-it--fourth-relayed-aside)
 * [🔴 My falsifier never identified the offset — the half I called a formality did](#my-falsifier-never-identified-the-offset--the-half-i-called-a-formality-did)
 * [The 92.3 %-versus-49.6 % gap: same numerator, and their filter is not applied](#the-923--versus-496--gap-same-numerator-and-their-filter-is-not-applied)
+* [🔴 Correcting my own correction: none of the 1 530 is a question without content](#correcting-my-own-correction-none-of-the-1-530-is-a-question-without-content)
 
 <!-- /INDEX -->
 ## P0 — the exporter, 2026-08-28
@@ -15258,3 +15259,46 @@ is the same shape as a negative reported without its reach.
 — neither of us was wrong about the disc. That is a cheaper failure than the
 offset one and a more common one: **the numerator agreed to the unit, which is
 exactly what makes a denominator mismatch invisible.**
+
+## 🔴 Correcting my own correction: none of the 1 530 is a question without content
+
+I told them their denominator held *"1 530 questions that were never asked"* —
+records with no timed keyframe, where *"does `+0x08` equal the largest keyframe
+time?"* has no meaning. **I did not check that, and it is wrong.**
+
+| of the 1 530 excluded | |
+|---|---|
+| **no timed keyframe at all** | **0** |
+| **timed, every pose at t = 0** | **1 530** |
+
+**Every one of them has a largest keyframe time. It is 0.** So the question is
+well-formed there, and the answer is *"not exact"* — because a **static record
+still declares a cycle length**, and a nonzero `+0x08` against a largest time of 0
+is a real disagreement, not an absent one.
+
+📌 **Which makes their 49.6 % defensible rather than mistaken.** Two statistics
+over two populations:
+
+* **92.3 %** — of records whose largest keyframe time is **> 0**.
+* **49.6 %** — of **all** nested records, static ones included.
+
+**Neither is the corrected version of the other.** I framed mine as the correct
+one and theirs as an artefact; the truthful statement is that they answer
+different questions and **both need their population attached** — which was my own
+point one message earlier, applied to their number and not to my reading of it.
+
+⚠️ Their cause diagnosis is still right about the **mechanism** — `.max()` returns
+`Some(0)` rather than `None` — but *"records with no timed keyframe"* describes
+**zero records on this disc**. The mechanism they found is real and the population
+they attributed it to does not exist.
+
+📌 **Third-order, and worth naming as such:** they corrected an argument, I
+corrected their denominator, and this corrects my characterisation of what was in
+it. Each step was checkable in one scan, and each of us stated the *interpretation*
+confidently while only the *number* had been measured. **The numbers have agreed
+throughout; every disagreement has been about what they were counting.**
+
+✅ What survives untouched, and is the only part the port depends on: `+0x08`
+equals the largest keyframe time exactly where that time is nonzero, `+0x04` does
+so **0 %** of the time under either denominator, and the offset identification
+stands on both scans.