SAsaurik·Nov 15, 2020
I find the most interesting discussions surrounding this protocol are about whether or not it should support deniability / repudiation of messages. The Off-The-Record messaging people--including specifically Ian Goldberg--were unhappy that this was a non-goal, and the reasoning on the mailing list at the time was frustrating (that deniability can be used by "terrorists" to dodge investigations); but, I have also seen them have better arguments on their issue tracker (about power imbalances... though this argument was also controversial).
https://mailarchive.ietf.org/arch/msg/mls/ZJ4e78obXSdYWnxmsN...
https://github.com/mlswg/mls-architecture/issues/50
In The Messaging Layer Security (MLS) Protocol