Proposition: Numerical permanence does not prohibit future regrowth

Removing a masking reparameterization while retaining its current zeroed tensor does not by itself impose a permanent zero constraint under later optimization. There are losses for which a zeroed coordinate immediately becomes nonzero under a subsequent gradient step.

Proof. After mask removal, take a scalar zero parameter $w=0$ and loss

A gradient step of size $\eta >0$ gives $w^{\prime }=\eta$.