Fred,
I don't know the technical answer to your question, but I have linked in with at least fifty different profiles, with uncountable generations back. Just this morning, working on a side line, I linked into one line that added four generations. Sometimes one needs to search, and YOU know what I mean with the variant LNAB, etc, but the links are out there, especially when you get back into the 1700-1800's colonial American, and also in Europe.
Hopefully, some one with more tech savvy can answer your question better than I.
Nae.