That assumes that you can cut through armor if you are just real strong, which isn't necessarily the case.
That seems to mean stamina, not strength (not necessarily the same thing) although in comic books and so on I guess they often go together.not to mention fencing has little to do with a battle there superhuman strength means hes not going to be fatigued by the constant combat which will give him a huge advantage.
But even in battle, 'fencing' skill still matters very much. It's a myth that you just hit harder or the strongest guy wins. Maybe better for games or whatever genre context you want to stick to the fantasy though.
G