I agree that solo PvP you use disc, but we're talking about multiboxing and having to AoE heal like crazy since your toons are likely bunched up and you need to play many roles at once. That's the biggest strength of a priest, I thought, was the massive easy AoE heals. My locks and priest will likely always be on top of each other, and in range of holy nova, so I was curious why go for CoH. I guess if I don't need to get the 41 point talent then that allows me to go deeper into the disc tree