U asked why is wasnt contantly used to begin with this is the answer wether liking the skill or not isnt factored ito it . Its its practicality that it the factor . The effects are good not a single person is going to debate that . They look really good listed not a single person is going to debate that either . Wether it is worth it to use with god aweful long cooldown and extremely short duration is a different matter all together .

Example lets say to make this easyer for you a attack hits for 100 then u add the 300% what do u get ? 300 its really not that much compared to a regular dps output or even a whm.

All that effort and time taken to repeat an attack a dps does at regular is it worth it when you can instead use the space to either increase aggro generation to get a steady aggro flow or increase defense to take pressure off the healers