"It seems that this sort of design issues can be solved using threshold values under which users simply cannot accurately acquire a target" "['non', 'non', 'non', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con', 'con']" "paper quality"