Well that's still using php-cgi and it's still too slow!
No, it is not using php as cgi if you selected fcgi. How do you know that its using php-cgi, as phpinfo is always showing identical results for cgi and fcgi. if you want to test it, you will have to check it with ps aux. fcgi is as fast as mod_php, you can test it with apache bench. Also be aware that you have to wait a minute until you test again.
So the solution is still to use php-fcgi, you hack is not nescessary and its highly recommended to not use it!
To further speed up php scripts, intall eaccelerator or xcache.