In EU4, if anything, stacking some modifiers is exponentially better. Interest per Annum and Admin Efficiency are the obvious gamebreaking ones.
-1 interest per annum means 25% less interest, then 33% less interest, then 50% less interest, then 75% less interest (because of the hardcap at 0,25). 25 admin efficiency is -25% cost, then -33% cost, then -50% cost if you play Yuan and reach the magical 75 admin efficiency.
Completely offtopic, but when I read the title I thought this would be about that.