Conjecture on permanent tracking-error control by online adjustment of alpha

Let $y$ be the system output, let $y^*$ be its reference, and let $\alpha$ be the adjustable parameter in the variational model-free Lagrangian. The tracking error is $y-y^*$.

Permanent tracking-control conjecture. Under certain conditions, still to be defined, the Euler–Lagrange equation applied to the variational model-free Lagrangian establishes the possibility of controlling the tracking error $y-y^*$ permanently by online adjustment of $\alpha$.

The claim proposes a variational basis for model-free control, but the conditions required for the Euler–Lagrange argument are not specified in the source, and its resolution is therefore open.