re: a title negative that survives its own cross-check

Three earlier "the title never appears" claims came from instruments
later found broken -- a stale pixel oracle, a 41 s sampling interval, a
freezing stream. This one carries its own evidence.

title_probe_xchecked.py restarts its capture stream every 30 s AND prints
its reading beside an independent `import` grab every 60 s:

  1851 frames in 560.2 s = 3.30 fps
  cross-checks 9, disagreements 1
  max glyph 0

  t= 62s stream   6.05 | import   0.07  disagree (a fade, logos mid-transition)
  t=123s stream   7.40 | import   7.49  agree
  t=183s stream   8.18 | import   8.29  agree
  t=243s stream   0.23 | import   0.10  agree
  t=311s stream  89.68 | import  89.51  agree
  t=371s stream  80.97 | import  81.58  agree
  t=426s stream 117.43 | import 117.72  agree
  t=487s stream  77.71 | import  76.25  agree
  t=546s stream  70.43 | import  70.55  agree

Eight of nine agree within 2%, fps held at 3.30 with no collapse to 1.60,
and the surface moved through dark and bright phases. So the frames were
live: over 560 continuous seconds from launch, sampled 3.3 times a
second, the interactive title's green (A) plate never appears while the
game renders throughout. The final frame correlates 0.0145 / -0.0047 /
0.0102 with our title / main menu / EXTRAS renders -- attract-movie
content, not a UI screen.

Why remains unknown. live-title-press-a.png with its 753 glyph pixels
proves the title was reachable from this container on 2026-08-28, and
clearing the shader cache fixed the black surface but not this.

The two emulator-side questions (gamma control, 8AX vs ptbase) are
therefore blocked on a characterised failure rather than a suspicion.
Neither blocks the five menu screens, so I am returning to static work;
the probe is committed for whoever picks it up.

METHOD: a probe that cross-checks itself turns "no result" into a result.

docs/re/METHOD.md

@@ -544,3 +544,10 @@ agent's loop prompt, i.e. nowhere durable. See [`README.md`](README.md) for the
   "2 391 frames, zero hits" reads as overwhelming and collapses to nothing once
   the frames may all be the same frame. Sample count is not evidence of coverage
   unless the samples are known to be independent.
+* **A probe that cross-checks itself turns "no result" into a result.** Three
+  successive "the title never appears" claims were withdrawn because the
+  instrument was broken each time. The version that finally held prints its own
+  reading beside an independent grabber's every 60 s — 9 checks, 8 agreeing to
+  within 2 % — so the negative arrives with its own evidence that the frames were
+  live. Building the cross-check into the tool costs a few lines and is what
+  separates a measurement from a silence.