[top-posting damage repaired manually -dM]
>>> Such configuration makes verification of DKIM signature (and
>>> DomainKey Signature) fail.  So, anti-spam measures which use DKIM
>>> signature won't work with it.
>> Only if the DKIM signature covers the Subject:.  [...]
> It doesn't make sense that something in the subject line should break
> DKIM.

Oh?  Why not?  Aren't manglings of the Subject: just the sort of thing
DKIM is designed to detect?

> Are you saying that all of the bigger lists out there are "damaged"?

No, though (depending on what they do to mail thorugh them) I might
hold that opinion.

> Surely you subscribe to some of these damaged lists?

If you mean lists with [listname] Subject:-header tags, yes, I consider
them damaged.  (Is this "all of the bigger lists out there"?  I don't
know.  It's few of the lists I subscribe to.)  I subscribe to a few of
them, for which the perceived list value to me is high enough to make
me ignore the annoyance.

> Not all users want to be sophisticated with respect to the type of
> mail client / filter software they use, just to handle special,
> behind the times, geeky cases such as this.

"special", "behind the times", "geeky"?  Name-calling will convince
nobody of anything - except, perhaps, your inability to muster real
arguments to support your case.  Identifying list mail by out-of-band
means such as distinct headers, rather than shoving it into something
the sender can forge and the recipient can hardly help but see, is a
Good Thing in my opinion.

> I am using Thunderbird, which in every situation but filtering this
> lists mail, does the job well.

Then perhaps Thunderbird is...special?  Behind the times?  Yes, I'd
call it behind the times, if it can't identify lists based on anything
more reasonable than a subject-header tag.

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