Tensor-to-scalar ratio posterior distributions with a fiducial tensor-to-scalar ratio of r = 0, as derived with Commander when fitting SiFeC simulations using the one-component MBB model for six different instrument configurations. A χ² statistic is reported for each configuration, indicating the map-level goodness of fit. All results are derived from a sky fraction of f_sky = 60%. The red dashed lines correspond to the median distribution from the ideal one-component MBB fit to an MBB simulation shown in Fig. 7 and serves as a reference.