In order for Mailing List messages to pass SPF, DKIM, and DMARC checks, the List From Address: really needs to be the List Address. The problem with this, at least in SmarterMail, is that if the person who posts does not give a signature or identifying information, you do not know who posted. Other mailing lists I am on get around this by having the List From Address: be the List Address, but for the name, puts "List Name on behalf of Poster Address"

For example, let's say I have a mailing list called user-chat@mercury.net. If I set the List From Address: to be the List Address, the From: line will be:

From: <user-chat@mercury.net>

If someone posts without their name, signature, or other identifying information, you don't know whose "speaking."  The From: only identifies the List and gives no indication of the Poster.

How other mailing list software helps that problem is by doing this:

From: "user-chat on behalf of david.sovereen@mercury.net" <user-chat@mercury.net>

In case some people want the anonymity to use the mailing list address and not reveal the poster (I can see this being desired in one-way e-mail blast type of mailing lists), I would leave the option of List From Address: List Address as-is and create a new option... something like List Address on behalf of Poster Address to enable this improved functionality.

I made a support request for this improvement, and demonstrating that there are other SmarterMail operators who would like this improvement may help raise it up the priority ladder.  If you are also using SmarterMail to host group mailing lists and would benefit from this improvement, please vote for this topic.  Thank you for your consideration.

Dave