One of the fun parts of creating the obfuscation was writing the subroutine to "decrement" a word (eg. "Jus"-- => "Jur").

It wasn't clear initially clear how many "increments" I was going to want to make, and if it turned out to be more than a few (as it certainly did), I needed to a subroutine to do it.

This was what I ended up with:

sub decrement_word {
    my ($pword) = @_;
    my @vals = map { ord $_ } (split //, $$pword);
    my $idx = $#vals;
    while (1) {
        if ($vals[$idx] != ord('a') and $vals[$idx] != ord('A')) {
            --$vals[$idx];
            last;
        }
        if (0 == $idx) {
            shift @vals;
            last;
        }
        $vals[$idx] += 25;
        --$idx;
    }
    my $word = join '', map { chr } @vals;
    $$pword = $word;
}
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It's too bad, I think, that a word "decrement" isn't part of the Perl language, at least for the obfuscatory potential it would provide. ;-)