I think SomeGuyVT hit the nail on the head, with a (simple?) solution that wouldn't require reworking the queueing system. (I'd still like to see them make adjustments to the queue system, but that would require more work, obviously) Add something to the UI, that indicates when players swap from the roles they queued for. Let it be a persistent icon, on the raid frame, in addition to . So, if you do have an occurrence where all 6 healers swap to dps, then it's obvious to the whole raid, and can be sorted out before a wipe. Or, if the raid wipes with, say, 3 healers, and some people drop, and more come in, then it's obvious who the folks are, who should either volunteer, or be asked to go back to heal spec.