This fixes both those bugs, but there may be other edge cases.

The fudge wasn't necessary once I fixed the real problem:) Yes. 'ZZZZZZZZZZZ' is a fudge, but I am re-using mapNM which is a utility routine that wasn't specifically design for this case and this is the 'cheap fix' to flush the pump.

#! perl -slw
use strict;

sub mapNM (&@) { 
        my $code = shift; 
        map{ 
            local( *a, *b ) = \( @_[ 0, 1 ] ); 
            $code->(shift); 
#        } 0 .. @_ - 2 
        } 0 .. @_ - 1
}

sub strcmp{ 
    my( $p, $b ) = ( $_[2]||0, 0 ); 
    $p++ until $b = substr( $_[ 0 ], $p, 1 ) 
                cmp substr( $_[ 1 ], $p, 1 ); 
    $p * $b; 
};

my @names = sort map{ join' ', map{ $_ = ucfirst } split '[^a-z0-9]+',
+ lc } <DATA>;

my %abbrev;
print "@$_" for mapNM{
    if( defined $b ) {
        my $n = 0;
        while( exists $abbrev{ $a->[ 0 ] } 
            or $a->[ 0 ] eq $b->[ 0 ]  
        ) {
            $n = strcmp $a->[ 1 ], $b->[ 1 ], abs($n)+1;
            if( $n ) {
                $a->[ 0 ] .= substr( $a->[ 1 ], abs $n, 1 );
                $b->[ 0 ] .= substr( $b->[ 1 ], abs $n, 1 );
            }
        }
    }
    $abbrev{ $a->[ 0 ] } = undef;
    $a
} sort{ 
    $a->[ 0 ] cmp $b->[ 0 ] 
} map{
    [ join('', m[([A-Z])]g), $_ ]
#} @names, 'ZZZZZZZZZZZZ';
} @names;
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