Well, for one thing, it will end up being grounded "backwards" (my word) cause it will end up being bonded to your boxes and/ or lights via the mounting screws, that have to be grounded.
So kind of a moot point.
Now, as to whether the "tin" needs to be like formally bonded, the Code knowledge guys will chime in about that.
Tell us if it is a steel frame, or wood pole barn.
My understanding and past practice is to bond to ground the steel frame of a metal building, ( course the tin is then grounded by means of the attachment screws to the frame) and also the tin in a wood frame building, but I am unable to cite Code. Marc