I just started my first Epic TR and chose Arcane Alacrity as my past life feat. I intend to stack this 3X to reduce my necro cool-downs by 10%. Today it occurred to me that I am already using an Epic Destiny ability from the Magister line (spell school Familiarity) that reduces cool-down time. So, I am wondering if the Epic past life feat and Epic Destiny ability stack. Does anyone know? Also, seeing as these are percent-based reductions, how do they stack? Additively vs. multiplicatively/compounding?