The cluster theory works, as I've seen other family lines move around the country together. The Root and Stanley families individually and eventually connecting the family lines in Southeast Michigan. My Norwegian lines along with many friends and relatives immigrated from Norway, all settling in Southwest Minnesota.
The process of cluster research is a little more time consuming, but well worth the effort. It paints a more thorough picture of the family group. It is exciting when you "spy" a familiar name in the census, a name that in later years became a member of the family, as occasionally neighbors would marry (saw this a lot in Spring Grove, as young m