» Sat May 28, 2011 7:02 pm
The same effect doesn't stack (e.g. wine and beer). Different effects that modify the same value do stack (e.g. Mentats and beer)
Percentile increments are another matter though, they can either add a plain 10 to a percentile value (e.g. increase the critical hit chance from 25% to 35%) or increase a value by that percentage (e.g. increase the critical hit chance by 10% from 25% to 27.5%)
So depending on whether you add or multiply, 10% + 25% can either be +35% or +37.5% (1.10 * 1.25 = 1.375)
The priority comes into play when you used mixed calculations: 50 + 10 * 1.25 = 75 but 50 * 1.25 + 10 = 72.5