Ha! I know this one! (I think...)
My family name is Shew, pronounced like SHOE, but is of Scots origin. The older folks pronounce it SHOW.
"Sheugh" was once used as a spelling by a company trying to sell my mother siding. She threw a fit, screaming "any fool would know we are not called "SHOUFF".
As to the accuracy, I cannot tell you. But she was really P*ss$d at being called a ditch!
Mikal