  We consider the stability of position control of traveling waves in
reaction-diffusion system as proposed in {[}J. L\"ober, H. Engel,
arXiv:1304.2327{]}. Instead of analyzing the controlled reaction-diffusion
system, stability is studied on the reduced level of the equation of motion for
the position over time of perturbed traveling waves. We find an interval of
perturbations of initial conditions for which position control is stable. This
interval can be interpreted as a localized region where traveling waves are
susceptible to perturbations. For stationary solutions of reaction-diffusion
systems with reflection symmetry, this region does not exist. Analytical
results are in qualitative agreement with numerical simulations of the
controlled Schl\"ogl model.
