Warning: I do not use FastCGI. My understanding of it's functionality may be wrong. Please take with appropriate sized salt particles

Short answer: No.

Longer answer...

As I understand FastCGI operates by separating out the one-time initialisation code from the per-request code.

Your FastCGI script then does the one-time initialisation once, then sits there taking requests and passing them onto the per-request code.

You get the speedup by only running the script "once" (it just sits there forever in a infinite loop serving requests) so you avoid the perl compilation hit, and the one-time initialisation hit.

So, unless you rewrite you code in the form of:

initialise();
while(FCGI::accept() >= 0) {
    serve_request();
};
[download]

you won't get any speed advantage.