vs rps you can actually split and it makes for a great strat. that comp is so used to relying on both link and swap that if two targets are low they dont know what to do half the time. Have your hunter fake going spriest by purging and dmging with normal dmg rotations but not blowing anything major and when the rogue opens have just the hunter swap off. You'll get all major defensive cds if your hunter has 2 eyes. when he vanishes just swap back priest when the rogue reopens use hp and major cd's as an indicator who to swap on or pressure.
ret healing is good enough that if both dps are being kept in check with having to play defensive you can live through anything they do
Against Rog/Sp/Rsham we use Fist of Justice on Shaman while fearing the Priest and try to land the kill on the Rogue, follow with Scatter>Trap on Shaman after FoJ and Silencing shot on Priest. Repeat every 30sec when FoJ/Fear is ready again. We mostly go Priest while waiting for cds.
Those Rog/Sp/Rsham teams that I've met just swap me (Priest) while they fear my partners, I just try to stay away and use Spectral Guise as soon they land fears on my partners, doesn't work all the time but you got trinket and painsup when you fail.
And remember, Roar of Sacrifice > Rogue/Sp damage.