FamilySearch.org's blog had a recent article entitled, "Finding More Ancestors." The concepts reviewed in this post are extremely valuable. The idea is that by adding sources to existing ancestors in the FamilySearch Family Tree, you will find additional individuals who have been missed and can then extend the family tree. There is much more that can be said on this subject.
The first step that needs to be taken when approaching the FamilySearch Family Tree is to verify, through adding sources, each of the ancestors in your particular lines. Although millions of sources have been added to the Family Tree, there are still many, many ancestral lines where there are no supporting sources at all. Automatically jumping out of an end-of-line situation, i.e. where a fan chart shows a missing ancestor, often makes the unsupported assumption that all of the ancestors named on the fan chart are correct. This is very frequently not the case. Although it is possible that the names in the Family Tree are correct, it is impossible to rely on those conclusions absent some validating sources. All of the users of the Family Tree need to realize that the information in the Family Tree came from a variety of contributing databases and that none of the information has been independently verified. Entries without supporting sources are nothing more than pure speculation.
The degree of uncertainty in the Family Tree increases with each additional generation of ancestors who are not verified with sources. Adding the sources may seem to be tedious and unnecessary, but the fact is that by adding sources, you are increasing your chances of finding a person for whom the Temple ordinance work has not been done, while jumping back in time without supporting sources dramatically increases your chances of working on families that may be entirely unrelated. The incorrect link in the ancestral chain may not be evident and in fact, may have been perpetuated by a mistake in your own pedigree if you received a file from a relative.
Here is an obvious example where a portion of the Family Tree has been extended with very conflicting evidence:
The parents of Amy Huntington (or Hutton) named Mr. Hutton and Mrs. Hutton, have no sources, however, there are alternative parents listed as Simon Huntingon and Amey Standish. A quick examination of the entries in the Family Tree shows that there are obvious duplicates for William Stewart and that a search for the apparent duplicates shows no results. The duplicates, are William Stewart LZBC-JLP and William Stewart L6M4-WR3. Both of these listing for William Stewart show as husbands of Amy Huntington LZBC-JPJ. When an attempt is made to merge the two by ID number, the results is an error message that the entries have been previously identified as "not a match." The reason given was "The information is to (sic) different." Here is a screenshot of the error message:
The information for the duplicate entries show the following:
William Stewart LZBC-JLP born 14 October 1742 in Perth, Perthshire, Scotland and William Stewart L6M4-WR3, born 5 November 1740 in Lunenburg, Worcester, Massachusetts, United States (Even though there was no United States in 1740). The death dates for the two individuals are different but the death place and burial information are the same. The first entry for William Stewart shows no parents and the second one shows parents as another William Stewart LCTJ-BFD born Abt 1700 in Salem, Essex, Massachusetts, United States with a wife named Margaret Sanderson LZZX-PRK born on 20 January 1704 in Allendale, Northumberland, England and her death on 8 March 1755 in Peterborough, Hillsborough, New Hampshire. Was William Stewart born in Massachusetts or Scotland? Do we have the same person or two different people? Both are married to Amy Stewart.
Now what does the fan chart indicate?
First, a look at their descendants. Here is a screenshot of William Stewart LZBC-JLP and Amy Huntington LZBC-JPJ:
Notice all the red warning icons.
Here is another descendancy view. This one is the William Stewart with the LCTJ-BFD identification:
This view shows the father, William Stewart LCTJ-BFD with a son named William Stewart L6M4-WR3. The William Stewart and Amy Huntington LZBC-JPJ do not have any children showing. So, depending on which of these you believe, either there will or will not be any children. Compare this screenshot showing no descendants of William and Amy to the one above.
Now to the fan chart. In this case, I started with myself and worked my way back to these people.
You can click on the images to see more detail. To add to the confusion, the William Stewart shown is LZBC-JLP who are shown in the previous views and his wife is shown as having the Mr. and Mrs. Huntingdon as parents. So let's suppose that you are seeking a person to research, given the idea that looking at the fan chart is going to help you decide. You see a lot of blank spaces on the Stewart and Huntington lines. There are a few sources listed for both William Stewart and his wife Amy Huntington, but the William Stewart listed is the one shown born in Scotland and the Amy Huntington line is shown without known parents. The Descendancy view of this couple shows none of the problems that I have reviewed above.
Because the duplicate entry for William Stewart was marked as "not a match" it does not show as a problem even though both entries have the same wife and the same burial information.
I could go on and on, this is only the tip of the iceberg, so to speak, of the problems associated with using a fan chart as the starting point for finding new family members without working out the problems of the Family Tree leading up to those individuals showing an end-of-line.