Cousin Connections

[Ron]

I have a question that I cannot answer. I am trying to connect two lines going back about 10 generations to a common ancestor. My line is complete to my first ancestor to Canada/North America, however the other line is blocked at the Acadian dispersal time, arounf the late 1700's.
Someone in this other line says that DNA testing would not be good enough to prove our common ancestor as there are "too many cousins" involved.
Can this be a facter in "diluting" DNA tests. In other words he will not subscribe to a DNA test because he says we have cousin connections elsewhere in both our lines that makes us interelated.
Would this be true?

Ron

[jigg]

It deosn't matter if cousins are interelated, if two Y-DNA match then they came from the same source