Why this matters

It records a change in measurement coverage. It explains why incomplete evidence prevents a public tier.

Picture it this way

Picture a crowded room with a narrow exit. Undertow asks whether many holders could try to leave while the doorway is getting tighter. An unscored market stays unknown; it does not become calm.

The catch

Undertow replays use truncated current-vintage observations restricted by dated knowability, not publication-vintage validated backtests. PARTIAL does not imply illiquidity, and NORMAL does not guarantee executable depth.