What I meant to write, with corrections:
And if the meaning "to go back [in a string]" is established
[...] "back up" seems to me the one expression that people dealing
in code point conversion and string access would use in this context.
then "to back up" in that particular meaning has also become a
technical term (so I guess it's defensible to keep it in TUS), even
though it's derived from figurative usage of what you do with cars
and horses.
But I also just searched around a bit in books and articles, and it
doesn't seem like "to back up" is used much by algorithms or even string
algorithms people. If it's really default usage in the domain of "code
point conversion and string access", that's a small and Unicode-heavy
community.
Stephan
