lucy24 - 10:07 pm on Feb 24, 2012 (gmt 0)

so adding the code and getting rid of the index.php would be more beneficial than keeping it in the long run do you think?

Yes, but you also have to make sure that all your own links point to

/directoryname/

rather than

/directoryname/index.php

The redirect is added as insurance, to pick up outdated links from other places. If your internal links remain in the wrong form, the search engines will keep crawling everything forever.

That applies to all directories everywhere, not only your front page.