IIRC, most browsers of old would not start rendering the document until it had been fully transmitted from the server and the connection closed, so a sleep() in a CGI would just make the connection appear to "hang" while unnecessarily eating up resources on the web server.
in reply to Sleep - settle an argument?
From the Perl perspective, the default sleep() can only do integer seconds while Time::HiRes lets you use fractions. Other than that, nothing has changed AFAIK.
Time flies when you don't know what you're doing