When you get a tree match against a private profile, you're still showed enough information to determine if there is a match, and are able to request a merge. However when you have a tree conflict and are redirected to (or open) the merge duplicates view you are unable to stack any private profiles connected to the merged profile.
If you're lucky the private profiles may come up as matches and you can request the merges that way, but more often this is not the case. The duplicate profiles attached to merged profiles are much more likely to be a match than those presented under tree matches, so it would make sense to be able to request merges on these.
Of course the owner of the private profiles would still be able to reject the merge request, or just leave the profiles stacked but unmerged as they wish.
This would allow for a much cleaner tree, less notifications that you can do nothing about, and will bring more pending merges to the attention of curators in cases where the owner of the private profiles is inactive (with the added benefit to them of the entire tree being already stacked instead of just some profiles).
- Richard.