I'm quite sure they have. Why don't you go find it. I realize you said you looked, but clearly not hard enough.
I've noticed that there's a post on the "Shadowpriest Theory Craft -- 3.2.2 Edition!" thread that compares and outlines the benefits of the different professions for shadow priests. However, I haven't found a recent post on the healing threads that's been updated with info about the different professions.
I'm currently looking at rolling a shadow/holy priest and given that I'll likely be using both specs roughly 50% of the time, has anyone crunched the numbers to determine how the different professions fare in a dps/heal environment?