? about dual wieldFollow

Unless it specifically says "hits with both weapons" I'd assume it is a Main Hand weapon attack.

Also bear in mind that the Reaver is essentially a tank build and Paragon is essentially a DPS build. From a purely DPS point of view, you'd likely focus a lot on using Paragon abilities for damage while having your Reaver DoTs ticking away. Personally, whenever making a Warrior DPS build, I see two possible options for any build that doesn't have Champion or Paragon as it's primary soul - go dual wield by putting more left over points into Paragon, or go two-hander by putting more left over points in Champion.

From a personal-experience perspective, I just don't see the damage from dual wielding unless you put a decent chunk of points into Paragon. Two-hander builds seem stronger right off the bat. But for an end-game, true Reaver build, you'll most likely be tanking, and you'll most likely be using a one hander and a shield.