Monks have been designed such that whether they equip one 2H-weapon or dual wield two 1H-weapons of the same iLvl and stats they do effectively indistiguishable damage. This is true for their tank spec and their melee dps spec.
For a long time Blizzard has tinkered with melee classes (especially Frost DKs) trying to make one 2H ≈ two 1H but always one has been better than the other.
Is not now possible to finally make the choice between one 2H or two 1H arbitrary for melee classes like Warriors, Death Knights and Shamans?