If typical LACs enabled typical students to graduate with less debt than state flagships, they would have more interested students. A post a while back in this thread compared the NPC of a poster resident in Indiana and found that IU Bloomington was slightly less than Earlham. People in our midwestern area are well aware of the NPC of area LACs compared to state flagships. LACs can work hard to get close to the flagships. Few are able to be less for a broad swath of students. Having said all that I still think the shift in desired majors is the biggest effect.