I've played as a pve disc priest since I was level 10, which was about 2 years ago. I went through some of the changes in BC, but primarily raided and adapted to changes as they came out in WOLTK. This is just another change - of all the differences in disc healing: heal>fheal, hasting POH with additional DA bubbles and so on, I'm finding adjusting to smiting the most counter-intuitive.
I tend to look for a lull and smite to 5 stacks, pop then just heal away from there - I know that weaving it will "work magic" for me once I adjust, and I eventually will. That's what its all about though, simply adapting to the changes. I'm not overly efficient at it yet, but I hope to be. I've seen the discussion concerning "to take or not to take" but I think we are being led this way, and until there is a convincing gear/spec argument that leads me away from evangelism/archangel I plan to stick with it.
I weave smites into my healing (normally hasted under BT) as much as possible and maintain a 5 stack of evangelism so i know i can pop Archangel and get +15% healing when i need it most. With the changes to divine aegis AA + PoH can pull off some huge heals (and shields) and really help on heavy aoe (or on mechanics like infest)