  Recent experiments exhibit a rate-dependence for granular shear such that the
stress grows linearly in the logarithm of the shear rate, \dot{\gamma}.
Assuming a generalized activated process mechanism, we show that these
observations are consistent with a recent proposal for a stress-based
statistical ensemble. By contrast, predictions for rate-dependence using
conventional energy-based statistical mechanics to describe activated
processes, predicts a rate dependence that of (\ln (\dot{\gamma}))^{1/2}.
