On a substantive and ethical level, I tell my students to take on faith that if you were to do all of this and take all this into account, if you were to apply the conflict of interest and the disqualifications rules, it could make it extremely difficult or many of the firms involved in these matters to avoid being conflicted out; especially, if the parties and the kind of firms involved were not dealing with these conflicts and issues until a problem arose. The question I ask my students again at this point is what could be done. What could be done proactively from a contractual matter to try and avoid these sorts of problems? And one of the answers to that is, as part of retainer agreements between firms and their clients, advance conflict waivers as a way to fend off an advance or try to fend off an advance potential disqualification if conflicts of interest arise down the road.
Becker, Edward R. "Using Advanced Conflict Waivers to Teach Drafting, Ethics, and Professionalism." Transactions: The Tenn. J. Bus. L. 18, no. 2 (2016): 660-70.