Why all this speculation. Obviously the aircraft experienced a contact with the ground out of operational limits resulting in a bad landing, obsolute the only type of bad landing....
Respect the operating limitations of the equiptment you are operating, understand this through and through and the odds of safe operation are on your side.
The point being made is that the MD-11 is the only big jet that during a heavy landing enough to shear the gear, rolls on it's back because the wing breaks off. Just because you do a really bad landing that should not be the result.