Expect that all targets will have 400 resilions. So lets say that yuor base crit that your stats are showing wouls be 20% crit... +10 from talents(not shown in the crit calculation) - 10 from 400 resilion on the target = 20% total crit crit. That meens that you should crit as often as you will proc a Lightening overload. And normaly 1 of the 4 bolt will proc.. or crit on each wave. Its the little extra dps that i found bedder then the 50 or so more spell dps..