FWIW it has a specific purpose in Unicode: compatibility.
"it should be possible to convert from x to Unicode and back and get the same result" is a design principle, for a large number of x. Adding SGML to the list at a cost of one code point is reasonable.
FWIW it has a specific purpose in Unicode: compatibility.
"it should be possible to convert from x to Unicode and back and get the same result" is a design principle, for a large number of x. Adding SGML to the list at a cost of one code point is reasonable.