I think it is very likely that there are voting rings and sock puppets here on HN. If so, it would cause a distortion in the scores awarded to all the content, sometimes up or down, depending. Therefore anything that helps fight that would improve the site by more honestly gauging the quality of submitted posts and comments, which then improves the S/N ratio.
How to do this exactly? Not sure. But I'm confident that fighting it more will improve any site.