That's true:

#!/usr/bin/perl
use warnings;
use strict;

use Unicode::Normalize qw{ normalize };

my $char = "\N{LATIN SMALL LETTER U WITH DIAERESIS}";
binmode *STDOUT, ':encoding(UTF-8)';
print normalize($_, $char), ' ' for qw( D C );
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Running the output through xxd:

00000000: 75cc 8820 c3bc 20                        u.. ..
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