Personally cases I see are:
1. I either sign all myself OR these guys <list domains> sign on
my behalf
a. In some special cases it can also be I sign all myself AND
one of these guys <list domains> will also sign it
2. I always sign if it comes from[*] <list email address> but
otherwise I may not add a signature
3. I always sign when it goes to[*] <list email addresses> but
otherwise I may not add a signature
[*] From and To are general concepts here and do not necessarilly
imply "From" and "To" header field specifically
Gets a 'Thumbs Up' from me... I like it a lot.
Regards,
Damon Sauer
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