Since you are such a pro (nope), it shouldn't be a problem for you to do two very simple things:
1. Elaborate, why there are so many MDPS gear pieces with Expertise (take notice that Blizzard stopped making mistakes of putting random stats on gear like in Vanilla and TBC).
2. To record how you just autoattack boss dummy from behind with 0 Expertise (your character stat sheet should be visible) and get ZERO dodges, any combat tracker like Recount or Skada will do it.
Till that, please do not post whatever bull**** comes to your mind on forum, especially advising other players