A few months ago I was trying to write an article about secondary stats for disc. In the middle of that I found I kept flip flopping; couldn't even really decide for myself what works best. I discovered firsthand that what works flawlessly in one raid group can make you look like you're totally clueless in the next.
On top of that I couldn't make simcraft duplicate my ACTUAL healing behavior. At best all you could ever really do is make the simulator follow some ideal behaviors. For example, PoM on CD and PoM always gets fully consumed. PW:S right on time for every single rapture. No easy way to make some amount of activity go towards PoH and some amount of activity go towards GHeal.
In other words, very difficult to draw conclusions from simcraft. So I kind of gave up.
But now the simcraft devs have made it easier for us. As of the current CVS revision you can put heals at high priority and then limit their use. In other words, you can make simcraft duplicate the healing behavior on a WoL if you are willing to do a little bit of leg work. Our goal: match a simulation to a WoL report, so that we can get a realistic look at stat weights for that particular priest, with his particular healing behavior, on that particular fight. It has the potential to end the stat debate, because now anyone will be able to sim for themself just like a DPS would.
There will be a lot of people that sim haste on top. There will be some people that sim crit on top - trust me! There will also be people that sim mastery second.
It's still not going to be perfect, but it'll be a hell of a lot closer to the truth than it used to be. Today I'm going to try working up a blackthorn HC model, will share results when they're done! I want to make it pretty easy for anyone to do the same thing with their logs.