So i guess im asking if these work together or are they separate, and can maximum reduction be achieved with just one or will i need to balance the two?ive read the formula page and understand it but do i need both for my damage reduction warrior build?
And also will the formula page be updated in the upcoming update?(just yes or no will do 
)
Does no one know even a little on the subject?
I don’t think anyone really focuses on resists. The best thing to do there, in my opinion, is just have the one element thing going on throughout all your gear and use the Unity mythic on your ring. Buuttt… that’s kinda pointless, imo. Just focus on Damage Reduction, Dodge, Armor, and health. Afaik, Damage Reduction and Dodge work for magic and elemental damage. Not positive on Armor.
Thank you, your advice is much appreciated and it gives me some sort of direction for my testing 
Oh, Perseverance. It’s a Legend Affix. Reduces damage from DoT, caps at 50%. Attainable through Ruby. Not sure what gear it spawns on.
EDIT: The stat caps at 50% on one piece. I believe it can be put on two pieces at 50% for a 100% reduction in DoT. Which is probably a bug. Kinda OP.
Also, I’m sure you’ve seen this, but it may serve as a decent guide for your test: