riposte_reps_default() with Huber's psi replaced by the raw tanh(y) that
the "Power for Policy" proposal used (as do manytestsr's pIndepDist() and
pCombCauchyDist()), for reproducing the proposal's tables exactly. Prefer
riposte_reps_default() for real outcomes, whose scale tanh(y) does not
respect.