I knew the mobs in the Limlight gorge are a real challenge for on-level players to solo them. I have a level disabled lvl75 mini with all the crazy gear and I could only defeat limlight gorge mobs in redline-dissonance and only when there was a rock i could kite around, using stuns, bubbles, and mobile heals.
So, well aware of the survivability of the yellowline beorning, I decided as soon as I hit level 68, to take it out to the Limlight Gorge to face the challenge of killing a Huorn. Being 7 levels below, most of my attacks were deflected and the huorn hit me hard with a lot of crits and devastating blows. Here's the 13-minute fight:
This fight felt amazingly easy. I could even chat while fighting, which is unfathomable on the other classes I tried this sort of fights with. I can conclude that I didn't test the limits of the yellowline's survivability at all here.