Bug on the dual wielding

Ive just reach the titans grip mastery, but when i wield my second weapon, my overall damage reduces..

i know that titans grip reduces 90% the damage of the weapons but im dealing more damage with 1 weapon that with 2.

for example, with 1 two-handed weapon my damage is 350-450, when i wield the second one (weapons with same damage) it decreases to 290-390.

so my bassic attacks goes from 370 to 340 or less... why is that?

Ps: the damage becomes red when i wield the second one.

thanks guys

You seem to know that Grip reduces physical damage dealt, so why is it a surprise to you that your damage is lower?

That said, do keep in mind that 290-390 x 2 > 350-450.

The damage becomes red because that's how the game shows your stats when they are reduced. They go green when increased.