I know that the Warrior has an increased drop chance (75%?) for legendaries when you kill him while being on the mission. Thus people kill him and reset right after using the moonshot (or make their saves read-only) if he doesn't drop the Conference Call for example.
If I am not mistaken the same is true for the final boss of the Tiny Tina DLC wherein you can Alt+F4 without freeing the queen in the end if there is no suitable drop.
Which other bosses have an increased drop rate when killed for the first time and is it recommended to use this method of farming them with the increased drop chance?