Aside from CoH/PoH spam (which doesn't work very well in 10m, when you have a druid spamming rejuv/wg aswell), what can holy do better than disc Themos?.. I know holy can do "just fine", but why settle for that when you can be exceptional as disc? With the way rapture works atm, you have almost endless mana, using inefficient spells to make certain people don't die is not an issue as disc, because mana regen is over the top. Doing that as holy would cripple you in the long run.