Never encountered the reset thing, that's quite odd.
I have however had the yellow thing on me, when I'm tanking Zorn. As the guy above said, since Zorn is rooted (and stops attacking his tank) during his yellow circle throw - it shouldn't really be an issue, as long as the tank is aware that it can happen to him. Myself I was very much shocked, started running towards Toth and then died.
It does kinda suck if said tank is an Assassin though, as he cant leap back to Zorn, which may cause positioning problems.
There are no positioning problems. Zorn is rooted until he throws the rock. If a tank gets the reticule, he runs it over, drops it and moves back. Without leaps, by the time he gets back, Zorn is walking again.