Although there are subtle differences in the approaches taken by the two groups, one can make a reasonably direct comparison between Kulkarni et al. (2011) and Noble et al. (2011). Both groups used ad hoc but reasonable cooling prescriptions in post-processing to convert magnetic stresses into radiation. By treating the dissipation as local and thermal, disk spectra have been generated for a nonspinning black hole by Noble et al. and for black holes with a range of spins by Kulkarni et al. From these two works, one concludes that spin measurements systematically overestimate the spin, that this effect is most pronounced at high inclination, and that the fractional change in is independent of . The deviation of from unity is of order ten percent. However, the state-of-the-art analysis has been achieved by Zhu et al. (2012), and its findings differ appreciably, as we now discuss.