Calculations:
You have a base CC of 30%
Full unstable gives 20% CC
At Combat 16 (the level required to use unstable) you would have 8% additional CC from combat skill buff
Reforging all 4 pieces to Fierce would give 24% CC total
That's already a total of 82% CC.
Sharp reforge on a legendary sword gives 20% CC bringing your total CC to 100%. (CC can't go above 100)
Of course if you are using something like raider axe or aote you could put pure on 1-2 pieces to get CC up to 100%, but adjust well since Fierce gives more damage than Pure.
Btw if you are using an epic sword, which Sharp gives 17% CC on, you would get a total of 99% CC but that can easily be solved by reaching Combat 18.
