if the knockback is not affected by diminishing returns..... think staggered knockback! A new way to deal with the annoying melee... also don't have to face them to use it... so its a good way to deal with melee who try to exploit multiboxers' inferior facing (at least i feel inferior when it comes to facing my toons in the right direction), combined with fire nova totems =D.

Also, if the knockback effect stacks, 5 of em would knock them back 10 yards if used at the same time! lol!