Talk:Earth Release: Added-Weight Rock Technique

Effect
What limits would this ability have? I mean Earth Release: Earth Spear gives the body an almost impenetrable defense, along with augmented offense, or an duration of about at least a minute (I say at least since that is about the time he had a hand thrust through his chest). Would this jutsu have a similiar duration, because then it would be highly effective. Granted Earth Spear may seem insufficient basis, but the level and devastating effect of the two seems similiar. Or is it limited to only when he has the hand seal activated?