The Last Piece Falls Into Place? -- Merge Comes to FamilySearch Family Tree?

Without any fanfare, the merge function shows up on FamilySearch Family Tree! I got the notice as a comment to one of my posts. This is the last big piece of the puzzle going into place. The selection shows up as a menu item called "Tools" with a link to "Possible Duplicates" on the Individual page of a person in the file with duplicates. Here is a screen shot of one of my ancestors with the selection indicated by the arrow:

Good news, clicking on the link lists a number of possible duplicates. Here is the results for this ancestor:

Bad news, clicking on an obvious duplicate brings up and warning notice, "These two people can't be merged." No explanation, no qualifications, nothing. Despite the good news, I am essentially back to space one.

I know that this particular person exceeds the arbitrary limit imposed by FamilySearch on the number of individuals that can be combined in New.FamilySearch.org, so perhaps there is a similar limitation in Family Tree? Or there is some size limitation or another?

Does this render the entire program useless for me and thousands of others in the same situation with huge numbers of duplicates? Stay tuned folks for the next exciting episode. Will James Tanner be shortly out of the FamilySearch Family Tree family?

My best guess at this point is that all of the wrong relationships have to be resolved before anything else works.

----time passes---

After working through an almost impossible tangle of wrong parent/child relationships and deleting those that showed Sidney Tanner as the child of his grandfather and/or grandmother, I tried the merge again. No luck. Untangling the Gordian's Knot of relatives makes no difference to the merge function. The two identical people cannot be merged.

Patience is virtue. Will FamilySearch untangle this conundrum? Will I ever be able to use the FamilySearch Family Tree program? We are still in the stay tuned mode.