I imagine that the mailing list is Bcc:, with themself as the To:. This would allow for such a setup. Of course this isn't "socially decentralised" but I doubt

I imagine that the mailing list is Bcc:, with themself as the To:. This would allow for such a setup. Of course this isn't "socially decentralised" but I doubt that's what most people are referring to when they talk about decentralisation.