A couple of points:
* Although civil aircraft can land at weights above MTOW, they are neither designed nor certified for that.
* Landing gear impact is a very complex event in which horizontal speed relative to the ground is important. Landing gear and backup structure are designed principally to three cases which occur during the touchdown: maximum vertical reaction, spin-up and spring-back. The spin-up and spring-back cases are influenced by the horizontal speed and do design certain parts of the structure. Manufacturers consider a range of landing speeds (including 0!) when deriving design load cases.