It would be helpful to move from 'managers' of profiles toward 'contributors' to profiles ... and that list can include both the creators of the merged profile *and* those who have modified/edited/added-to the profile.
The term 'follower' can still provide a function (as it does today), but adding the functionality of listing 'contributors' may help a lot (and that can be, if you want to get fancy, by either some measure of the 'volume of contribution' or by the 'last contributed' date-time). If you use that latter approach, inactive contributors will get pushed toward the end of the list -- and the list would instantly point to those who did the most recent changes without having to review pages of revisions in detail. The 'send mail to 20 most recent contributors' could be much more valuable, too.
What about those 'managers' who just "inherited" profiles from another user? (e.g.: account closed due to being deceased or leaving Geni). They should still be listed as a 'contributor', but should be added at the END of the list, not at the beginning. The person who's account was closed should then be also moved to the "end of the list". (Thus, if only one initial 'contributor', that would leave the new 'contributor' first in the list, but as any others added or updated content they would move to (or be added to) the front of the list.
I would suggest that the person completing a merge *not* be added to the 'contributor' list. (nor the "Geni" user, either, although both of those would still show up in the Revisions list.)
When the other profile and relationship fields (e.g.: marriage, work, schooling, etc) are changed (even if not currently under revision control), the person 'contributing' those changes could also be added to the beginning of the 'contributors' list.