You're actually very much mistaken about Skyrim. In Skyrim, dual wielding melee weapons allows you to do the extremely powerful dual wield power attack by holding down both the left and right mouse buttons at the same time. You can also do the dual wield normal attack by just clicking the left and right mouse buttons at the same time. But you will do extremely high damage with the dual wield power attacks. The whole is absolutely greater than the sum of the parts.