You mean when the two Drauger come out to play?
If you focus on one of them, then you may be able to burn him down before the second one aggros on you as you will be out of range if your careful. The guy in this video aggro's both of them. But I would take as much out of one of them as possible before dealing with both at once. Move around and make them come to you. They are not that quick.
https://www.youtube.com/watch?v=Xvo7_MF5mTk