I have to say I have never come across a single confirmed instance of there being any connection at all between the name Gillespie and the names Clasby and Glasby in 20 years of looking, I have a lot of scepticism on the whole hypothesis. It looks to me like wishful thinking on the part of some frustrated researcher at some time in the past.. Clasby has been a distinct surname too long, I think. However, I am very far from being any kind of expert on the "Northern Group" I think you would probably have more luck if you looked at the names CLEASBY and CLASPER, both common up there, as well as Clasby and Glasby, as I have come across instances of those names rendered as Clasby/Claspy in transcription. I could have sworn you once said Edward's father is listed as James(deceased)and his profession (tinker?) I do not recall the details. Could you confirm these as the details on the Kenny/Clasby marriage certificate? My personal feeling is that this family are immigrants from Ireland. Some Clasbys from Hampshire settled in Ireland in the 1600s and went native, only for their descendants to return to England in the 19th c, and also of course emigrate to the US and other places.