Formula for damage taken?

[Slappah]

Yes, and remember the higher our defense goes with higher ilvl gear ie heavensward.
The more damage foresight will mitigate, since it scales with our defense. Will be interesting to see how high it gets.
I believe the last time someone calculated mitigation from foresight it was in the 7-9% ballpark, could have changed since then.

But all stats will be growing. Along with enemies getting stronger too, so in reality foresight is still only going to give you 20% defense, it won't become op because of us getting higher ilvl.