Yes it will work, but the bracket is used because the lens is so heavy that it will bend the rails on the camera.
Look at the side of your camera fully extended and you will see that there are two small rails with teeth that hold up the front of the camera. If these rails bend then the front is not parallel to the film plane and will throw the focus off.
It's a good idea to use this lens with that bracket at all times -- the bracket screws to the bottom of the camera and will allow the lens to move in and out (the lens rests on a couple small wheels on the bracket) and will hold everything and not allow the front of the camera to bend down.
Needed, no. Good idea, yes.