Connectors aren't going to help the spot welds holding the front rails on. The trans crossmember and front rails are separate components spotted together, not a single unit. It will help alleviate the levered rotational force transmitted to the trans crossmember
Taking the inners out makes the rails an unsupported lever. Science guy time, take a 2x4, 5 feet in length, hang 10lbs out one foot, then hang the weight out 5 feet away, quite a difference.
There's a lever point in floor pan attachment point where the front and rear weight of the vehicle is applying force. Like taking the same 5' 2x4 and placing it on top of cinder blocks at each end. Stand in the middle... it'll bow, same effect without the inners.
