Iceheart seems to be the only monster set left with it's proc condition being a percentage of a percentage, i.e. 20% chance only when you crit. This will be further hit next patch with crit value being harder to come by. Removing the 20% chance, and just having it proc when you crit will have little to no effect in PvE, (as currently with a few DOTs running in addition to your direct damage will keep it proccing on cooldown), but make it more viable in PvP.