its complicated to say the least. The guide says its simple. Well, if it were would you require this much text to explain it?
Diablo 3 Dual Wield Mechanics Guide
Given that three of the five Diablo 3 classes can dual-wield (Monk, Barbarian, and Demon Hunter), a lot of people have questions as to how dual-wield works in Diablo 3.
Dual-Wielding is a pretty simple mechanic in Diablo 3. When you equip a weapon in the off-hand slot, you automatically get a 15% increased attack speed bonus for using two weapons. This is the only direct bonus you get from dual-wielding.
When you are dual-wielding weapons, you alternate attacks between them for most attacks. Each weapon retains its own damage and attack speed. For example, if you have a 1.0 attack speed weapon and a 1.5 attack speed weapon, your main-hand weapon will swing first at an attack speed of 1.15 attacks per second (15% bonus from dual wield) and then your next weapon will swing at 1.725 attacks per second.
If we convert these numbers, this means that your main-hand will swing, there will be a .87 second delay (1 second / 1.15 attacks per second) and then your off-hand will attack. Once your off-hand attacks, there will be a .58 second delay before you swing with your main hand again.
Since you alternate attacks when you dual wield weapons, as a general rule of thumb your weapons need to be somewhat close in damage or else you may actually lose damage when you dual wield. Imagine if you have a 20 DPS club and a 6 DPS club in your mainhand and offhand slot respectively. Even with a 15% attack speed buff, you still have to swing that weak offhand weapon one time for every time you swing your mainhand weapon. This will likely lower your DPS since it is slowing down the number of times you are swinging your much more powerful main-hand weapon.
D3 Dual Wield Mechanics Guide – Exceptions and Oddities
While as a general rule of thumb you want to find an off-hand with as high as DPS as possible, there are a few exceptions to the rule. I have put together a video that demonstrates a few things which modify the best weapons to use when dual-wielding:
In the video above, I talk about dual wielding and two stats of interest: +Weapon Damage and +Attacks Per Second. Here is the general gist of the video along with some other important stats that you should know about when choosing your weapons for dual-wielding:
+Damage. This stat is not only important for your off-hand but rather both weapons. This is a stat which flat out adds damage to your weapons regardless of attack speed. The faster the weapon, the bigger the DPS bonus you get from it. Faster weapons tend to be better for dual-wielding, particularly in the off-hand slot. There are a few downsides to fast weapons, but that is a topic for a later post.
+Attacks Per Second. This stat increases the attack speed of both weapons, not just a single weapon. This makes any very fast weapon with this stat very strong to use in the off-hand slot, particularly when combined with +damage and attack speed rings. I have not seen it on any magic or rare weapons in the beta, but then again that only covers low-level items. You can find it however on white-quality weapons with the prefix “Balanced”. In the video, I have a Balanced Simple Dagger, though I have seen much higher DPS Balanced Broadswords and Balanced Shivs that would work well too.
Faster Offhands Can Be Weaker Than Slower Off-Hands. Since a fast offhand takes up less of the attack cycle than a slow offhand, you can get away with not using
Other Stat Bonuses. Stat bonuses like increased attack speed (on armor , not weapons), strength, dexterity, and other effects are highly prized on dual-wield weapons since they improve the damage dealt by both weapons. Sometimes a weaker off-hand with a lot of your primary stat will be a better off-hand than a higher DPS off-hand with no relevant stats.
Edit: According to Redditor Darouu, increased % attack speed bonuses on weapons only apply to that particular weapon, not to both weapons. For example, if you get 5% increased attack speed on your off-hand, your main-hand weapon speed will not change. +Attacks per second definitely applies to both weapons, so whether or not increased attack speed when found on weapons not applying to both weapons is a bug or working as intended is still up in the air. You should still seek increased % attack speed on rings and gloves when dual-wielding as this applies to both weapons. I would not be surprised if +attacks per second gets nerfed because right now it seems too strong for dual-wielding.
I hope that clears up a lot of the confusion about how dual-wielding works. Just remember that it doesn’t hurt to take a second to equip a lower DPS weapon with some interesting stats to see if it boosts your DPS. Also, check between different off-hands as your armor and jewelry slots change, particularly if you add on anything that boosts weapon damage or attack speed.
So... quite simple! Right? Right!!? Told ya ;P
Anyway, in my own personal experience 2handers are better. Why? Because of your abilties. All of them are based on your WEAPON DAMAGE, and since a 2hander's average weapon damage is much higher than a 1hander, the bonus you get for your abilties is therefore much better. i could clearly feel this when i went from 2x 1hander xbows to a 2hander xbow. suddenly only had to use multi shot 2 times to clear packs instead of 4. now having to cast multi shot 4 times does not only require twice as much time as 2, but it also costs twice as much hatred!
this is just my experience. might be wrong. please feel free to comment :)