It is if you need to iterate through the loop enough times!

How do you figure that?

If you're going to loop a million times, it's still only takes 0.0007 s cumulatively. It will only add up to 7 s if you do a billion passes of the loop. If you're doing something a billion times in Perl, it's going to take an hour, a day, or more. An extra 7 s isn't going to matter. This is the point where you offload the work to C or something, not move a my.