Let me quote selectively.
Steve Dorner writes:
I just spoke to a fellow with a very interesting email proxy system
that unfortunately works by using such []'ed cruft in subject fields.
I suppressed my gag reflex, because I understood why he was doing it.
Most current MUA's hide all headers except a specific few, so if you
want to communicate anything to the end user, the only way you have
to do it is by scribbling on those few visible fields.
...
A further step that would probably be interesting would be to simply
remove such strings from subjects displayed in message lists.
Could this be generalized as a recommendation to MUA's? I dunno. It
seems like a feature that's useful a lot of the time, and harmful
occasionally (eg, when there is real information inside []'s for some
reason).
Sounds like an arms race.
1. Proxy adds header fields.
2. MUA learns to show only a select few fields.
3. Proxy sticks information into subject using []
4. MUA learns to suppress [].
In step 5, the proxy must stop using [] and switch to something it's
more difficult to suppress.
The same situation applies to disclaimer/advert footers, I suppose.
Arnt