The Dowdeswell family of Temple Guiting (descended from John Dowdeswell and his wife Christian) spread out over time to Ashchurch, Hazleton and other places in that part of Gloucestershire. Unfortunately, there seems to be repeated attempts to connect this family with the family that settled in Guiting Power in the 1770's. The origins of the Thomas who married Elizabeth Hanse have yet to be proven, as the Thomas who was the son of John & Elizabeth and born in 1747, was buried in Temple Guiting in 1758.
This is not to say there is no connection, as John had a brother, also Thomas, whose movements I have been unable to trace at this point. The other possible link is to the branch of the family which was settled in Ford, and which seems to have disappeared after the death of the head of the family in 1729.
Due to the fairly unique nature of the name, I am sure such a link can be found. As yet though, no link can in my opinion be proven.