re: S00A.wmv confirmed off the running game -- the movie was never

ambiguous, the sampling was

Continuing last iteration's amber rather than starting something new. The
fix was already named there: stop using 5-second screenshots and record
the display.

Recorded with ffmpeg x11grab at 10 fps and matched every 0.5 s. Across
the 25 consecutive samples from capture 5.0 s to 17.5 s the S00A playhead
is strictly non-decreasing -- 1.0 through 11.0 s, advancing at
essentially real time -- with scores at or above 0.96 and four of them at
0.999 or 1.000 against a runner-up in the 0.78-0.83 range. S00A is the
top match on 23 of the 27 frames carrying signal. So MS00A -> S00A.wmv is
decoded from the manifest AND measured off the game, and the intro begins
about 4.5 s after A on the save slot.

The previous attempt's failure is worth its own METHOD line, because it
did not look like a sampling problem: it looked like weak evidence for
the wrong film. Sparse sampling produced contrast-23 frames, a playhead
that would not join up, and one frame preferring ADV. Sampling does not
weaken a signal gracefully; it turns it into noise shaped like a
different answer.

One aside recorded and not chased: in the S00A 5.5-10 s window, ADV also
scores 0.97-0.99 at its OWN monotone playhead of 33.5-37.5 s. Two films
matching strongly with two consistent playheads is not noise -- it reads
as the boot movie being a trailer cut from the story cutscenes, which
also explains why the sparse run kept flipping between them.

docs/re/METHOD.md

@@ -196,3 +196,10 @@ agent's loop prompt, i.e. nowhere durable. See [`README.md`](README.md) for the
   ~1 GB free with swap exhausted. Budget dynamic experiments to fit in ~2 minutes
   of guest time, take the measurement early, and never read a disappearance as a
   guest crash without checking the log tail for one.
+* **When a frame-match will not resolve, sample denser before doubting the
+  hypothesis.** Identifying a movie from 5-second screenshots gave contrast-23
+  frames, a playhead that would not join up, and a runner-up winning one frame —
+  it looked like weak evidence for the wrong film. The same question sampled every
+  0.5 s (`ffmpeg x11grab` at 10 fps) answered at **0.999 with a strictly monotone
+  playhead**. Sparse sampling does not weaken a signal gracefully; it turns it
+  into noise that looks like a different answer.