Training Trick: Fine-Tune Only the Last Layers to Avoid the Moving-Target Problem

Sauers_ · x · 2026-10-18

Sauers was surprised how well the experiment works — "the models just want to learn." Iterating on the training strategy: fine-tuning only the last couple of layers preserves the probe-induced difference the model picks up on, avoiding a moving-target problem; more training data improves generalization. The idea came from steering-probe experiments at Anima Labs: maybe he was measuring not just steering effects but the mere presence of a probe — zero-strength steering might already feel slightly OOD to the model.

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