Re: [ietf-smtp] broken signatures, was Curious

"Kurt Andersen (b)" <> Tue, 21 July 2020 23:04 UTC

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From: "Kurt Andersen (b)" <>
Date: Tue, 21 Jul 2020 16:03:52 -0700
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Subject: Re: [ietf-smtp] broken signatures, was Curious
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On Tue, Jul 21, 2020 at 3:25 PM Michael Richardson <>

> any system that knows what
> some header is, (such as X-BeenThere or X-GRID-REF) *is* ought to rip that
> out as it knows whether or not its useful.

That's a highly presumptuous stance to take. Knowing what a header is and
making a judgement as to whether or not it is useful are not at all the
same thing. Amongst other relevant points is the question of "useful to
whom (or what)"? Something that is not useful to 99.9% of recipients might
be very useful to the remaining 0.1% (witness the current thrash in the
dmarc-wg regarding components within the 5322.From header field)...