A signature can be a way of identifying a relative when other details are scant or inclusive. The difficulty comes when the researcher does not really know if the executor of a document actually signed it or not. Some records genealogists use are original documents containing actual signatures and other times those records are transcriptions or record copies of the original documents. Record copies made in the day when transcriptions were made by hand don’t contain the actual signature–they contain a transcription of it.
Once in a while original records may not contain the actual signature of the “signer,” even when they appear to. This 1827 bond from Fleming County, Kentucky, contains the “signatures” of James and Enoch Tinsley. Their signatures look very similar. The “signatures” of their names look similar also to how their names are written in the body of the bond. Their signatures also look less “labored” than do the signatures of the other three individuals and of the witnesses.
All of which makes me wonder if James and Enoch actually signed the document.