Harry Soo has done 11 videos, experimenting with this. HE basically saves the trim from the brisket and throws that in a pan during the cook and mops his paper with it. What I like about his videos is he tries a few ways, and follows a method to improve his cooks, cooking several briskets and then judges them.
Here is the first video in the series of 11 on this subject..
https://youtu.be/XkacTTFcdJ4