Due to the limitations imposed by the FamilySearch.org Family Tree's ongoing connection to the now abandoned, new.FamilySearch.org program, there are still unresolved duplicates in the shared database. For example, here is a screen shot of my 3rd Great-grandfather's family showing three sets of obvious duplicates:
In each case, the possible duplicates are easily found by the Family Tree but cannot be merged. Here is the results of a search for duplicates for Sidney Tanner:
The challenge is that both of these duplicate entries are being edited with sources added. In each case, some of the sources are duplicates but some are unique to each of the two copies. Sidney Tanner KWJ6-DZX has 14 sources listed and Sidney Tanner LZXK-Y57 has 28 sources listed. All of the "Legacy" sources from new.FamilySearch.org are going into the entry for Sidney Tanner KWJ6-DZX and the latest changes for this version of Sidney Tanner were last made on 4 March 2015. The other copy, Sidney Tanner LZXK-Y57, was last changed on 19 April 2015. It makes me wonder if the people adding sources and making corrections are even aware of the duplicates, even though they are obvious.
Why choose one of the copies over the other to make changes and edits? What happens when the program gets fixed and the duplicates are merged? Which version survives. What if the person who finally merges these two duplicates fails to copy over all the information from the discarded copy?
How serious is this problem? One of the features of the new Puzzilla.org Premium version is the ability of the program to show possible duplicates in your family tree. Here is a screenshot of six generations of my family with the purple squares showing the possible duplicates. This took the program a relatively long time to calculate.
Now, some of these potential duplicates are not a real match, but there are others that cannot be resolved by merger at this time. But if I were to ignore these potential duplicates and keep working in the Family Tree, I would very likely create a future problem that may not be resolved correctly.
My experience also shows that there are likely many more duplicates out there that the Family Tree cannot detect. I have discovered additional duplicates using the Find function and even more from looking at sources. For example, if I search for additional individuals named "Sydney Tanner" I find 62 results including a Sidney Tanner MSSC-K9X who is "of Beaver, Beaver, Utah" and is a duplicate. However, when I try to merge these obvious duplicates, I get the following message:
I suggest caution in working with any ancestors that show up with unresolvable merge issues.