Yes, because it uses an array, and only one array.

What's even more important to me is that it's also decidely easier on memory. Every single array in Perl has a minimum overhead of about 100 bytes without even counting the individual scalars inside it (and the one holding the reference to it..). When you're trying to sort a couple dozen million elements with a Schwartzian transform, as I've had to, that adds up alarmingly. In comparison, this method is basically free in terms of memory cost.

Nitpick: you should really say 0 .. $#h when that's what you mean, as is the case here.