Incoming SMTP in the year 2017 and absence of DKIM

Wed Nov 29 21:13:27 UTC 2017

In article <88a1ae22-a5c1-dc46-caa7-cca813109e99 at tnetconsulting.net> you write:
>  - Requiring Reverse DNS
>  - SPF
>
>I'm not commenting about the viability of these things, just that they 
>are fairly well accepted and that they can trivially break mailing lists.

A mailing list sending with bad rDNS or bad SPF is a pretty cruddy
mailing list.  Normal lists put their own bounce address in the
envelope so they can handle the bounces, so their own SPF applies.

No idea why you think rDNS for a list's MTA is any harder than anyone
else's MTA.

R's,
John