Quantitative analysis of the precision achieved for the Stage II time-delay measurement as a function of the photometric precision of the fainter quasar image and as a function of the true time delay. All panels show results from the bias-free spl technique for the secure + plausible selection of rungs 2 and 3 after rejection of the catastrophic outliers (see text). Top left panel shows the metric P as computed using the uncertainty estimates δ_i without using . Top right panel shows the rms of the relative point estimation residuals without considering δ_i. Bottom left panel shows the average P obtained in each tile after selecting only the best half of systems according to the blind precision in . Bottom right panel shows a map of the χ² metric. In all panels, only tiles describing more than three light curve pairs are shown.