Main Hand and Off Hand - help me understand

Can someone explain me how works this passives?

1. increased Attack Damage with Main Hand
2. increased Attack Speed with Off Hand

If you're using 2 1h weapons, the left weapon is in your main hand. The right one is in your offhand. If you're using a skill that alternates weapons after every hit (say reave) and both weapons are able to use the skill, the attack with your main hand weapon will hit harder, and the next reave (which will be with the offhand) will finish faster.

Attacks using off hand will be faster, attacks using main hand will hit harder. (for skills that alternate hands/use specific hand)
For attacks that use both hands (dual strike/cleave) the increased damage will be added to the damage calculated from the main hand. The attack speed of these attacks is the average of the both hands.

Example: you have 100% increased damage and 50% increased attack speed.
You have two weapons with 1.0 AS and 100 base damage. (I'm not factoring in innate DW bonuses)
Using reave, you will alternate between these 2 weapons each hit. They both will hit for 200 damage at 1.5 AS.
Now with Ambidexterity passive, when you hit with main hand, the attack will do 226 damage at 1.5 ASD. When you hit with off-hand, you will hit for 200 damage at 1.7 AS.

If you use Dual Strike (whatever level it has 100% effectiveness at) you will do 400 damage per hit at 1.5 AS. With the passive you will do 426 (226+200) damage at 1.6 AS (the average of 1.5 and 1.7 AS).

thanks for clarification