The authors offer an alternative explanation for an article by Carey and Siavelis that suggests that the Concertación (center left coalition) presents lists with two strong parliamentary candidates since, as a government coalition, it can offer "insurance" —in the form of appointments to Executive Branch positions— to those candidates who assume a personal risk in favor of the center-left coalition and are not elected. Since the 2005 presidential elections were expected, at the time the article was written, to be more marked by the uncertainty of the outcome, Carey and Siavelis argued that "the Concertación cannot continue to guarantee their candidates (...) a position in the government apparatus." That would mean a greater obstacle in presenting pairs of strong candidates. This paper offers two alternative explanations of why the Concertación presents lists with more strong candidates than the Alianza (center right coalition) does. The first explanation is that the Concertación is formed of parties that represent two of the three historic thirds of Chilean politics. The second suggests that the Concertación is simply comprised of a greater number of parties than the Alianza. Despite sufficient evidence to support both explanations, there is insufficient statistic or methodology confidence to argue that the alternative explanations are better than those offered by Carey and Siavelis. However, it is likewise demonstrated that the argument they make is neither methodologically or statistically more plausible than those put forth in this study.