The buff to the wall of elements does not carry-over when you switch bars. That is, the buff from the weapon only happens on the bar where it is equipped. It was caught on PTS, but went live still not working. Unless this is intended, which makes it un-usable and unlike all the other dot centered weapons, especially other maelstrom (bow, two-hander) which also buff their weapon's line aoe dot but is triggered on cast and carry's over to the front bar for your rotation giving the buff for the skills duration.