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

Paul Smith wrote:
>   
> So, what would you want the recipient MUA to do with these. The 
> consensus seems to be that they should still receive them - so what 
> difference does the 'expires' make? Automatically moving them into 
> another folder when they arrive is nearly the same as automatically 
> deleting them as far as many users goes! Showing them in grey or another 
> colour doesn't stop people having to read them to see if they've missed 
> something important.

often you can tell from the subject line whether a message is something 
you actually need to read.  if the subject line of an expired message is 
shown in grey, that's just another clue to help the recipient decide 
whether to read the message or delete it.

> "confirm your subscription to list X in the next 3 days" is still 
> important if you receive it 4 days later. Now you know you need to try 
> again to get onto the list.

right, some messages become _more_ important after a given date...

it's at least possible that ordinary users might eventually learn how to 
use such things as expiry dates.  for instance, many of my younger, 
non-geek friends now seem to understand the value of Bcc.  I don't think 
that was true 10 years ago.

> "I'm out of the office until ..." may be important, you may have been 
> bad-mouthing a contact because they hadn't replied to you earlier, and 
> now you'll know why

a good example of why automatically deleting a message based on expiry 
date is a bad idea.

> "special offer valid until ..." may still be important from the sender's 
> point of view as a "buy our wonderful flying car for only $15,000 before 
> 30th July, look how amazing it is..." is still a good advertisement if 
> it's received on the 1st August, and the recipient may still want it 
> even though the special offer has expired.

yes, but most readers would not want it.  again, automatic deletion is a 
bad idea but when the reader sees the summary line of the advert in grey 
he'll likely infer that the offer has since expired.

I could imagine looking at the message summary in my ietf-announce 
folder and seeing some LAST CALL announcements in grey and others in 
black - and that would be useful in letting me know which messages to 
ignore.

(I could even imagine configuring my MUA to show a message in red if the 
expiry date were within say three days...but that probably wouldn't be 
the right thing for most messages nearing expiration.)

> 'expires' only makes sense (IMV) if it would reduce the mail to be read 
> by the recipient by getting rid of stuff that's absolutely no use any 
> more. 

disagree.  I think it's useful as a tool to help people decide which 
messages to read.   but my assumption is that other people do like I do 
and look at the subject lines of messages to decide which ones to read.

Keith