From what I understand after reading the match algorithm, this is slighly incorrect: residency's rank lists are only taken into account if there are more applicants who want to go to that residency than there are spots. If you rank an unpopular place with >5 slots and only 4 other people want to go there, then you would end up matched at that residency. It's only if you rank a very competitive place that the residency's preference list is consulted. Say 20 people rank Program X as their #1, but Program X only has 15 spots. The 5 people who didn't get into Program X would be the five lowest on Program X's applicant preference list.