THE PAYOFF
Joint features: blind. The delta: a clean flag.
Best single feature isolating the backdoor, at one middle layer. Same data, two ways of looking at it.
40x stronger signal
1.00 precision
~0.01 joint features
Best-feature isolation score (BIS)
Crosscoder (joint)
Diff-SAE (delta)
AI text/layout recreation from video frame; verify against source image.