Quote from frozenwilderness;1060575:
i always thought the % chance to roll a certain number was dumb anyway, good thing they fixed that
It's not bad for flame burst at least.
I mean when you execute the skill and it ends that's 5~6 seconds off because of the animation. It may be that you will CC immediately since the cooldown hits as soon as you CC, not when you CC then you use the skill.
So if you CC flame burst, wait for them to come closer or you run to the enemy and use it, most likely you'll find that your flame burst is quite active!