The idea is to have a means for Pro users to allow some kind of control over the way profiles are merged, instead of relying solely on Geni's internal rules for profile merging. This new capability would be less "restrictive" than a Master Profile designation (which is a Curator-only privilege), but it could also be applied to "Private" profiles as well as "Public" profiles.
See more details at this Geni forum discussion: http://www.geni.com/discussions/110082