Transport airplanes were certainly not designed for aerobatic maneuvers, yet a very few pilots want to do 'em anyway.
Flying these types is dead easy...fly it the way it was intended by the manufacturer...and it will likely keep you out of trouble.
To those that want to operate outside of the approved envelope...you might get what you have not bargined for, and quite frankly, unless properly trained test pilots, are nothing more than silly fools.