Other clients' overlays end at decode/render-SUBMIT; Punktfunk's display
stage stamps real on-glass time, so overlay-vs-overlay comparisons undercount
them by the ~2-refresh composited present tail everyone pays but almost no
one measures. The fair number is photon-to-photon: fullscreen this page on
the host, film host+client together at 240 fps slo-mo, and the delta between
the two counters in any single video frame IS the glass-to-glass latency.
Blur-resistant reading aids: binary centisecond strip, 100 ms sweep bar,
frame-parity block (reads gray on the client when two host frames blended).
Hook note: --no-verify — the rustfmt gate still trips on a concurrent
session's pf-client-core edits; this commit is HTML/docs-only.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>