We study the computation of the static quark potential under decimations in
the Monte Carlo Renormalization Group (MCRG). Employing a multi-representation
plaquette action, we find that fine-tuning the decimation prescription so that
the MCRG equilibrium self-consistency condition is satisfied produces dramatic
improvement at large distances. In particular, lattice coarsening (change of
effective lattice spacing on action-generated lattices after decimation) is
nearly eliminated. Failure to correctly tune the decimation, on the other hand,
produces large coarsening effects, of order 50% or more, consistent with those
seen in previous studies. We also study rotational invariance restoration at
short distances, where no particular improvement is seen for this action.Comment: 10 pages, 3 figures, 3 table