I blogged some months ago about iw.memberrreplace in this page. In some words, iw.memberreplace provides a tool that clones the security features of an unser to another one (ownership, DC creator, sharings, group membership). No more hassle digging around huge Plone site and hundreds of clicks to do this.
So I spend a couple of hours on that component to add the last details on that component. Et voilà, the last release of iw.memberreplace (1.0.0-RC1) fulfills now that PLIP: the original member can now be removed - if defined in a mutable users source.
I swear that in the future, I will read the open PLIPs before creating a new component ;o)