I loved the days prebc when you could find strength on cloth, Inner fire gave AP and Feedback was an on-melee-hit...
Then came the feedback nurf. I was saddened that I couldn't whack people to keep them oom. But popping it right before a mana burnoff with another priest was priceless. Or when a lock starts dot rotations on you.
And now it's gone! And now we're stuck with having to pws haste a quick burn once in a while.
I digress..but since I'm not on ptr..how effective is plain ole mana burn now? Since pretty much every mana class has talents that rapidly regen mana...
I'd say you only mana burn when you want to prevent someone from casting a certain spell, while that person is low on mana. Or as preparation for the real intense fights where people cast every GCD.
I tried dueling a resto shaman on beta (70, before premades). I had him oom after tons of grounding totems and earth shocks. Like 10 - 20 secs later he had 2k+ mana again :s