Complexity for case-sensitive systems

If one wanted to support case-sensitive systems, wouldn't it be enough
to require punycode to output only lower-case (or alternatively only
upper-case)?

Since the NAMEPREP phase of ToASCII would also lower-case any
ASCII-only segments, this would be enough to ensure that all
equivalent (case insensitve) non-traditional local parts map to an
identical ACE local part.

Of course, this would preclude the use of mixed case anotation...

	-roy