The effect of sink rate on the degree of preferential accretion. At sink rates that are too slow, mass builds up regardless of the sink method used, leading to erroneous torques and preferential accretion measurements. Once sufficiently fast sinks are employed, torque-free (δ = 0) sinks converge, while standard (δ = 1) sinks, if sufficiently fast, can lead to spurious results of any magnitude.