I raided as discipline from late BC through the end of Cata. Very broadly speaking, I remember holy and disc as comparable, with holy having slightly better throughput, with disc being more flexible and better at dealing with damage spikes. After healing War Within through leveling 5-mans, some batteground PVP, and just starting to dabble in endgame raiding again, Disc seems... finicky and difficult to manage, while Holy feels like near-faceroll "press buttons, heals go brrrr". I'm at iLvl 597, and I followed the Icy Veins guide on spec, gearing and rotations... and was struggling with Disc. So I spec-changed to Holy, and immediately after swapping, spending only a couple minutes putting spells on bars and going with the "least decision-making required" talents, I'm doing 20% more healing. And more than numbers, I can feel the healing get easier.
Is this anyone else's experience with Disc at present? Or am I likely missing something obvious?