A number of powers can be used while invisible. My main "HP Lovecat", Illusion-Empath Controller, has only 4 powers that draw agro. Without drawing agro She can stand in the middle of an enemy group and disable the 2 biggest Non AV threats, Perma-buff all 7 team mates with +22% to +34% Defense and Clear mind, as well as 900% Regen and 300% Endurance recovery 2/3 up time, and Perma AB for another 900% Regen on the "problem child" of the group 🙂. After that I seldom need to heal? Even so there have been instances where part of the team wipes and I have arrived just in time to throw a few heals or buffs as the last team mate dies and the enemy stands there and ignores me. In that case I throw Phantom Army, get the team rezzed and buffed and then kick ass. What Greycat said is spot on. Most of my time is taken up buffing and neutralizing the big threats. In most cases If I am healing then someone is doing something wrong.