Well, lets see, my crit rate with spears are 39 atm, and when I do Fury Infusion (Rank 9), discription says the chance of getting critical is increased by 22%, so when I do Fury Infusion, my Crit rate goes from 39 to 61, so 39+22 is 61...
So i think same would work for those CS, 50+12 = 62, but idk, I might be wrong lol