How did I never notice ALL hidden units get +15% to crit?

I played through the whole game on Very Hard, and I only just noticed something on a new playthrough. I never realized that ANY hidden unit gets a +15% to crit. I think it’s because by the time I was paying attention to crits more, I had already gotten mutations and hats and scopes and such, so I just paid attention to the overall number. On a new play, I’m stripped back down to basics and there’s a lot less to get lost in.

I found this to be useful for Dux, I have his crossbow with something like 20% Crit (sight that gives 15%) then Hat and Elevation, gets me to 90%, so on Stealth attack, I am 100%, his secondary is 30% (15% plus 15% sight), if I have elevation, im on 100% crit on loud attacks.

Really helps to be able to prioritise what weapons NEED to have the expensive 15% scope compared to those you can sacrifice some crit % for and make up with on the stealth ambush