Heres a tidbit I learned about target assist; Last nite I went back into Carn Dum with my kin.
At the exact same place that I caused a wipe earlier, I made sure I had my target assist on the leader of the group.
We cleaned out the area almost completely, with one bunch left to go, and My last button push caused the arrow to go exactly to the same boss as last time! :P
Still, this time, there was no wipe. We won the encounter. The leader must have been tabbing around himself and my last attack went off at the same instant. So, beware all hunters, it can still happen to you!