Cut the Wire: Collusion-Probe Ablation Effects Shrink or Relocate Under Format, Dose and Placement Controls

Linear probes read collusion from model activations with near-perfect accuracy, and ablating their directions at every layer produces large behavioural effects. How much of that picture survives controls? In Signal Table, a controlled steganographic betting game, we intervene on collusion-probe directions in four models from two families, with format-aware scoring, energy-matched orthogonal controls and a placement decomposition. Most of the large raw state-span effects decompose into format damage and generic capability cost. What remains is modest and bounded: a dose-dependent late-layer effect of 8-15 points beyond the control from the receiver's decoded-state subspace, in 7B only - recurrent across fresh messages, refit directions and new contexts, but absent at one predeclared cutoff and not transferring to 14B or 32B; and a clean early-layer effect of about 21 points from the detector direction. The standard logistic-regression detector direction is removable while collusion survives - the expected amnesic-probing outcome, since one direction rarely strips linearly-available information. A published collusion benchmark's steganography tier is separable by context length alone (AUROC 1.000): collusion and length cannot be told apart in that tier. High AUROC and large ablation drops are starting points for mechanistic questions, not answers.