The Shipley theory is claimed by family tree posters and not verified by me.
There was a Clews-Holder birth December quarter 1900, Ernest Clews, Sheffield. There was a 10 year old Ernest Clews, inmate, at Hollow Meadows Industrial School, Sheffield, in 1911, possibly indicating some impairment in family relationships.
Unless other Shipley family names also fall into place, the possibility of Ernest being connected might be worth exploring.
Can't understand why Robert Walter was given the name Clews at the daughter/stepdaughter's marriage. But then the first names Robert Walter fit. Sometimes hard to get absolute certainty.
According to the military history sheet for “James William Rotherham” “alias James Wm Flint”, 3/7283, he married Alice Maud Clews, spinster, Parish Church St Mary’s Sheffield. Witnesses were Frederick Jinks and Elsie Shipley.
There was an Elsie Shipley 15 in the household of Robert Walter Shipley & Eliza Agnes Shipley in 1911 along with Alice Maude Shipley 18 & 5 other children.
"When you found the Military sheets for James did you use the surname Rotherham or Flint?"
I was searching for anything about Alice Maud Clews. They indexed relatives names on the record too. A child's name was on the military sheet; and the mother Mrs Rotherham.
As a by the way, and a lesson in being wary, there are family trees on Ancestry that claim Robert Rotherham / Flint died in France in WW1!