Discourse looks great to me. Some other people are used to their mailing list subscription (mailman). There is a pilot installation https://discourse.wmflabs.org/ to test discourse as an alternative to the wikimedia-l mailing list. Reply by email and creation of new post has been set up for this discourse installation. It works. Now some one asks to sync wikimedia-l mailing list with the discourse forum.
What if some configures Discourse to use the same mail address as the mailing list? Would that work? Would that disrupt threads? What are your recommendations?