ComfyUI executes a node under torch.inference_mode(), so a descriptor read out of
the probe log becomes an inference tensor and autograd refuses it:
Trajectory probe intake failed: Inference tensors do not track version counter.
Every head stayed empty and the run reported "nothing learned yet" on every
generation — so the feature was OFF while looking merely untrained, which is the
one failure invisible from the outside: "not steering" is also what correct
behaviour looks like before enough ratings. Seen on a live rental with 73 runs
logged and zero of them trained.
The output value function's trainer already carries this guard; this one did not.
Also: the bucket-isolation test was measuring TRAINING accuracy, where a
few-hundred-parameter MLP fits 20 noise vectors perfectly and every bucket scores
1.0. It now holds rows back, which is the only version that can tell a head that
learned from one that memorised.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
