Depending on how seriously you play, you should really have channel ticks displaying on your cast bar. As far as I know you can use ElvUI, Gnosis or QUARTZ !!!!!!!!!!!!
It's pretty neat to clip your channels after you've just had a tick, rather than just before the next tick. It's a slight dps loss if you do it wrongly. Refreshing a Malefic Grasp before the last tick puts the final tick on your next Malefic Grasp, but it only copies over 1 tick, so effectively you save mana by refreshing Malefic Grasp/ Drain Soul as late as possible and cancelling them in order to redot or haunt (or whatever) just after you've had a tick.
Last edited by Filth the Warlock; 2013-01-29 at 09:21 PM.