  Control laws for selective transfer of information encoded in excitations of
a quantum network, based on shaping the energy landscape using time-invariant,
spatially-varying bias fields, can be successfully designed using numerical
optimization. Such control laws, already departing from classicality by
replacing closed-loop asymptotic stability with alternative notions of
localization, have the intriguing property that for all practical purposes they
achieve the upper bound on the fidelity, yet the (logarithmic) sensitivity of
the fidelity to such structured perturbation as spin coupling errors and bias
field leakages is nearly vanishing. Here, these differential sensitivity
results are extended to large structured variations using $\mu$-design tools to
reveal a crossover region in the space of controllers where objectives usually
thought to be conflicting are actually concordant.
