i think this is intended and not an exploit simply because its not that "great" of a benefit. Sarth 3d is doable if you got healers who can put stuff in there focus and just land there cd on the mt when 2d and 3d are up.
To me this "exploit" is like saying here to not die to walls in sarth just increase the max distance view command untill you see both sides. Its a nice trick but not an exploit for the fight.