Bob...shit/shite may not have been the best example to use because
shite isn't really a euphemism. It is a Brit-ism. Granted not all
Brit speakers use it but some do and it at one time it was the common
usage. In my writing I tend to have the Muggleborn/younger group use
shit, and the wizard-born/older generation use shite...especially in
dialog. (and no I don't really try to go over board with trying to
write accents..which is one of my pet peeves...too many stories with
Fleur's accent being so 'eavee there is absolutely no way in hell of
figuring out what she is saying)
One of my freinds in college was Brit born and raised in Hong Kong
(her parents moved there when she was 8 or 10), and she was one of the
ones who used it with great frequncy...