It is difficult for the leaves to find "difficult" people. I've tried the leaves quite a bit so that I am familiar with them and can reasonably answer questions about them. The leaves do make easy things easier to find. I'm not certain they are that helpful in other cases.
This pedigree chart comes from my Ancestry.com tree on my paternal grandmother, Ida Trautvetter Neill. There are leaves everywhere--most of them are from online trees and other extremely secondary sources that are not the focus of my research. It's pretty easy for Ancestry.com to match with people I've already located quite a bit on. That's the case with everyone on this tree except:
- Erasmus and Mary (Gross) Trautvetter
- Benjamin Butler
The matches for the Trautvetters are from online trees of other researchers. There's no match for them in Ancestry.com that is all that helpful.
Benjamin Butler is the more difficult problem--his name is more common than Erasums Trautvetter. I really don't know where Benjamin was born and the 1819 year of birth is only a vague estimate. Ancestry.com's leaves have a difficult time finding people in the pre-Civil war era for whom a person only has vague details. The fact that Benjamin lived in at least four states and two countries is not helping either.
The situation is this: It is difficult to program searches to effective "search" for ancestors on whom we have vague information. The approaches that will work on Benjamin (hopefully) include searching for his neighbors and associates, fully documenting his life and locating ever record he left behind, reading local history to get an understanding of motivating factors for migration, and maybe just a little bit of luck.
The Ancestry.com leaves aren't quite programmed for that.