Stability to the change in the observed polarization map. Data points shown in the upper panel are the BB^lens band-powers obtained from the cross-correlation of our SMICAB-mode template with the SMICA polarization map (red), and with single frequency polarization maps at 100 GHz (yellow), 143 GHz (green), and 217 GHz (blue), which were corrected for foreground and intensity-to-polarization leakage. Residuals with respect to the model in units of the 1σ band-power uncertainties are shown in the lower panel.