Re: Intent to revive "expires" header from draft-ietf-mailext-new-fields-15

Michael Welzl wrote:
> People are different. I'd be more than happy to let my MUA
> even silently delete past:
>
> * talk announcements
> * CFPs
> * special offers
> * "out of the office messages"
>   
(I'd happily just delete special offers and out of office messages, 
whatever the date is...)

The problem is that you don't know what an 'expired' message is about 
unless you read it.

People don't always do things right. So, a mailing list admin might well 
set up a 'you have 3 days to authenticate your subscription' message 
with an expiry date, or someone might send you a bill payment reminder 
with an expiry date of when it's due or whatever. You can be sure 
someone will use it in a way YOU don't want them to use it or think it 
should be used (or even ways that any standard prohibits). That's just 
the way people are... The amount of badly formed non-spam messages we 
receive is incredible, and the MIME/RFC822 standards have been around 
for years. If people can't get that right even now, you can guarantee 
that people will use 'expire' in an inappropriate way.

So, would you still be happy to have your MUA silently delete expired 
messages?

AFAICS, the only safe way to use 'expire' would either be for it not to 
move/delete messages at all (in which case, what's the point) or to have 
different rules handling expire differently from different senders (when 
you know how THAT sender uses it), but this would only be useful if you 
repeatedly got expired messages from particular people (which is doubtful)

(I do wonder, how important is this anyway? How often do you receive 
messages after they would have expired? The only time I can think it 
would be even slightly useful is if you've just come back from a 
vacation and haven't checked your mail whilst you've been away, but then 
a few CFP or talk announcements is going to be irrelevant amongst all 
the other thousands of semi-junk messages you'll have received!)

I don't have a massive problem with an 'expires' header, I just see it 
as, at best, pointless, and at worst, dangerous in the hands of an 
unthinking user (of which there are many using the Internet).

-- 
Paul Smith

VPOP3 - POP3/SMTP/IMAP4/Webmail Email server for Windows