Went to refute sylpheed-port's finding that their check-all allowance ("the pin
is not on main, so this compares two decoder eras") explained nothing, by
extending its reach past three screens. Found the premise is understated.
git rev-list --left-right --count origin/main...HEAD -> 0 171
main has nothing we lack; we are 171 commits ahead of it. Its tip is dated
2026-08-29, the pin tag is not an ancestor of it, and its ui_layout.rs still
reads "Keyframe time, or None for the group's last frame" -- the pre-fix
association that takes a pose's time from the NEXT record and leaves a group's
final pose untimed. That is the exact bug that left fade_quads.py stale and made
screen-transitions.md publish a 0.87-4.08 s fade-in for a 0.20-0.27 s ramp.
So "sync with main first" is currently backwards: main is the stale era, and
`git merge origin/main` is a no-op from any topic branch -- it says "Already up
to date" every iteration, which reads as "I am current" and means "main has
nothing". Do not pin to main.
The port's measurement stands: across their three screens the two eras render
identically, which is consistent with the association fix moving TIMES and not
pixels -- same signature as the .tbm and stale-sylpheed-cli findings.
Not settled: whether the eras render identically beyond three screens (the
disc-wide build-and-compare is not done), and why 171 commits are unmerged,
which is a human's call.
Also adds the METHOD entry the port offered: an allowance is a claim and it
decays; allow by NAME, never by COUNT, because a count cannot notice that a
different row started failing while the total held steady.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wuu56cE8vJGTBtn1ppsk8v
6afe0c4ab8