I found that when leveling I consistently finished fights with more health when I ignored the proc and just used Thrash and Shock, even when fighting golds. It doesn't matter much to me for leveling though; I'm sure Darkness/Madness would have been a better leveling spec, but I prefer to level with something close to what I use at end game to get used to it. I can see how in longer fights those heals add up, and it's not so important that I do good dps when in a group. If I had to level again, I'd just have kept it, and not used it except for the longer fights. There really aren't any great choices for those points in the tree anyway. I really do like using Force Lightning now and then. I want to like this talent, just wish it healed for a bit more.