I would say it depends on who is alive at least one healer or someone who can raise and he'll is well I've been you could probably salvage that and get people up you could think of it as a challenge if you will try to keep going.

I was in doing cutters cry recently and we failed the first time second time all 3 DPS and the tank died on chimera and all that was alive was just the white mage who solo'ed the last I think 20 percent on him, now that is what you call good ingenuity and thinking outside the box almost not all strategies a work of course but if a boss fight is somehow salvageable try to win the boss fight before saying ah screw it Iets just start all over again.