And healers could actually use LB when they know the party is going to wipe and not be called out for it. Even if it's nowhere near as powerful (say it only raises people killed within the last sixty seconds, or that it only raises them with 30% health and weakness), it's better than watching everyone die because the remaining tank or DPS believe that they can outlast and then LB the boss when you (being fairly intimate with health bars and their tendency to drastically shrink) know they will not.