Soloing Mordor with Yellow spec is doable, BUT:
- Most of the trait points in Yellow are either useless or unnecessary for soloing, so don't fill out the whole tree
- The entire rest of your build (gear, LI legacies, unspent trait points) needs to be damage-oriented
When I decided to make a Yellow build for soloing the tougher parts of Mordor, I really only took a handful of traits in the Yellow tree. Mostly I was there for the "freebie" traits in the lefthand column that give you defeat events and self-healing. The rest of my trait points went into Red traits to shore up my damage.
The end result is only a little bit slower than my Red line build but it can handle the wandering adds in dense enemy camps a lot more safely.
Oh, and to add some extra advice: Finesse essences are a really good investment.
Cainwen Ciaphas, Captain of Crickhollow, HERO OF MIDDLE EARTH!!!
I will not be pushed, filed, stamped, indexed, briefed, debriefed, or numbered! My opinions are my own!