Dear Assaf,
the reason for the unexpected behavior of 'fold', namely that specifying
--bytes doesn't make it count bytes, is evident after a look at the source
code.
When --bytes is not specified, the program treats '\b', '\r' and '\t'
specially. It assumes a tab width of eight (compile-time #define) and
attempts to keep track of what the output will look like.
This is absolutely not what I expected. But of course, when the program
was first written, the words byte and character meant the same thing
for printable characters. Printable bytes.
I will attempt to suggest an improved text for the man-page so that
others will not be surprised.
Mark