The activation diagnostic and severity rule

The source diagnostic uses the clean surrogate

For equal-size batches, it estimates

It omits challenge bias and noise. For general $p>0$, it also omits gain protection and offsets. At the default $p=0$ of the kindling routine, it equals the implemented clean, unchallenged diagnostic, but not the activation magnitude during the noisy biased challenge. For arbitrary unequal batch sizes, the source averages batches equally rather than examples equally.