
Originally Posted by
Miraun
Spira, I think either you or I is mistaken how Armor works in Diablo 3.
I'll admit most of my knowledge comes second hand from my roommate, who has almost completed Inferno (He took a week off from work for the release...). But he's an aggressive theorycrafter in any game he plays.
Dodge is the first line of defense for any attack.
Armor is the second line of defense, as a modifier for all incoming damage. Both Elemental and Physical attacks are subject to Armor's % reduction. While armor does have diminishing returns at higher values, having a stable, high Armor value is one of the most valuable ways to mitigate damage taken.
Resistances are a modifier applied AFTER armor. So if you have 50% reduction from armor, and then 20% reduction from resists, you will take 40% damage.
Then block is a static reduction based on block % and shield value, applied AFTER armor reduction.
While armor has perceived diminishing returns, the estimated time to live remains constant throughout it's progression. Therefore, while it may take more armor to raise 1% from 50-51% as opposed to 25-26%, it's because that additional 51st% is effectively reducing all incoming damage by 2%, while the 26% is reducing it by 1.33%, and the estimated survival rate remains constant, and the returns reflect this.
In the end, it's a balancing game, depending on what's right for your class. As a Wizard, there's no reason to go out of your way for additional resistances, as you'll be getting a decent amount from your INT. But if you're forced to choose between +300 Armor versus +100 Resists, the Armor would likely be more valuable.