At the moment, the condition is "no single Unicode code point." To
the extent that a single CJK ideograph can be expressed using a
single Unicode code point, this would represent the situation to
which you say you would object. I will dig through my notes to find
out why the "single character" condition was adopted -
Would you be able to explain why the condition is "no single Unicode
code point"? Whats the technical basis for that?
Ietf mailing list