Should "Index" be avoided as a controller name in CodeIgniter?

Is it recommended to avoid using "Index" as the name for a controller class in CodeIgniter? I've noticed that when I have an "Index" controller, its methods are called multiple times. Specifically, the index method is always called first, regardless of whether I visit a path that should be routed there.

Here's an example from the code:


class Index extends CI_Controller
{
    public function index()
    {
        echo "index";
    }

    public function blah()
    {
        echo "blah";
    }
}
When I visit "index/blah", I see "indexblah" printed. When I visit "index/index", I see "indexindex". However, if I rename the controller to something else (e.g., "Foo"), the issue doesn't occur. While renaming the controller is a workaround, I'm curious to know why this behavior is happening. Should I report this as a bug to CodeIgniter?

(Note: I haven't set up any routes in "configs/routes.php," and my "index.php" is located developer echat outside the CodeIgniter directory.)

I appreciate any insights or advice regarding this matter.