Thanks, Steve. It is just a name, yes, but I'd say a closer analogy might be if two people were called Steve Gardham and Steve O Gardham, and originated in the same country when there were no doubt not all that many popular figures to be made into ballads/stories. Then, I might think there was a fairly strong possibility of a connection.

What is it that suggests the Complaynt was referring to the Tam O lin ballad instead of Tam Lin, do you know?