Two cheap measurements settled a question three expensive ones had not, and both
of them contradicted the diagnosis offered for it.
The stated diagnosis was that the identity's expressive range had become the
bottleneck. It has not. A census of the identities themselves — no GPU, seconds
to run — puts mean distance between twelve songs at 0.43 with no near-identical
pairs and full coverage of every decision space: six of six fills, five of five
lattices, six of six protagonist forms, three of three element scales. The songs
are handed genuinely different designs.
The decomposition then asked whether those designs reach the picture, by holding
the container fixed and varying only the identity, then the reverse:
identity only 0.0299
container only 0.0557
both 0.1101
neither 0.0000
Identity is worth 54% of what the container is worth, against an instrument
noise floor of exactly zero, and the two compose to more than their sum. The
inversion works at the frame level. What it does not do is replace the container.
That corrects EPIC-3 §5, which proposed a song picking two to five stages on the
theory that shared content would substitute for container variety. Container
variety is the larger of the two effects and identity adds to it. Four stages
with a rich identity throws away the 0.056 the library was already providing —
which is exactly the shape of every measurement in this epic: stages have the
lowest floor of any arm and no advantage in spread.
The direction is therefore not a small set of stages. It is the whole library
consuming the cast: keep the sixty-one containers and make them draw the song's
content rather than their own. The migration was filed as a cost; it is the
payoff.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The Epic 3 arms appeared to show that a small casting roster was the largest
available win. Swept directly across 4, 8, 16 and 32 over twelve songs with
three pool draws each, the differences are 0.003 to 0.007 against a run-to-run
noise of +/-0.003 to +/-0.005. Pool size does nothing measurable.
The arms varied two things at once — smaller pool AND the same pool for every
song — and only the stages-versus-legacy comparison inside them held everything
else constant. That one still stands at +14%.
POOL_SIZE stays at 8, now on grounds the metric cannot see: about nine distinct
scenes in a video rather than seventeen.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Four stages, an identity layer, and an A/B that says the idea is right and the
reason it works is not the reason I expected.
A stage has no image of its own. It owns arrangement — a procession, a
constellation, a soloist, a swarm — and what it arranges comes from the track:
`castMain` and `castChorus` for the forms, `inkMask` and `inkValue` for the hand
they are drawn in. The identity generates a protagonist and a chorus with sides,
notches and hollows, plus an ink treatment of weight, edge, fill, outline and
posterisation. All of it travels as uniforms, so it is data rather than code and
a stage consumes it without knowing any other stage exists.
The protagonist IS the signature form rather than a second opinion about it.
They were separate draws in the first version, which let a track built on
hexagons put a round protagonist on screen — the signature said one thing and
the picture said another, and the shape trait stopped meaning anything for
stages. The cast now reads its geometry from the personality live and adds the
notches and hollows that turn a shape into a character.
Measured across seven songs, three arms, same instrument:
arm floor observed spread
stages, four of them 0.0801 0.1133 +0.0332
legacy scenes, four of them 0.0830 0.1122 +0.0292
the unrestricted generator 0.1058 0.1146 +0.0088
The prediction in EPIC-3 §7 was that sharing a cast would drop the floor
sharply. The floor did drop sharply — by a quarter — but nearly all of that came
from casting FEWER scenes per video, not from sharing content: the legacy arm,
four ordinary scenes with no cast at all, gets most of the same benefit. Stages
add about 14% on top of that.
That is worth knowing before building the other four registers. The single
largest available win was hiding in the roster size all along, and it costs one
number to take.
One result runs the wrong way and is recorded rather than explained: coupling is
+0.29 on the legacy arm and -0.18 on the stages. At twenty-one pairs neither is
distinguishable from zero, so it is a flag for a larger sample rather than a
finding.
Also fixed: a backtick inside the shader preamble's template literal, which
closed it and made every check page hang on "starting…" with no error in the
console.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
