If there's any kind of an objective, a tower to burn, a graveyard to hold/take, a flag to cap, or even a choke point to block...

I've been leap frogging the team towards the objective.
Basically move the others most of the way in that direction, leaving them close enough to Death Grip the rogue, if he opens on the toon.
If he saps one of the others, I move the previously sapped toon up some.

If he stays with the sapped toon, have not abandoned the old toon yet, but I suppose that is an option.
In the grand scheme of things, one toon then needs to regroup.
If we control a nearby graveyard, where the toon would rez then that is easy.
If we don't, then one toon gets separated, and that often leads to someone geting flagged as inactive.
Getting into combat is the best, as you cannot be sapped in combat.

If I'm at an objective, I could care less if the rogue wants to waste time sapping toons as I hold a choke or begin to cap something.
I do have a spread out mapped key, for the DK's and round-robin Blood Boil plus round-robin Death & Decay, which ensures my Paladin can support heal/cleanse anyone in combat nearby, and the DK's seem to like the wanton destructive spell usage.

My druids used to prioritize frost mages.
The DK's have added the addon Healers Have to Die, but prioritize rogues as their next target.