1. Mail senders SHOULD NOT generate group syntax.
maybe, maybe not. groups are useful. if we deprecate the group syntax
we will wind up reinventing it.
in general it seems like internet mail and MUAs are suffering from too
small a feature set - our tools aren't powerful enough to make email a
really effective medium, especially given the volume at which many of
us use it. which is not to say that we should keep useless features,
but groups are useful. IMHO more people would use them if MUAs
supported them better - not just parsing them but providing good UAs
for them.
at least both Apple Mail and gmail are being actively maintained, so
there's hope that they can be fixed soon. (though if I could figure
out how to get apple to listen to bug reports, I'd be giving them an
earful...)
2. Mail receivers are urged to test that they can parse empty groups,
since several current senders generate that, e.g. "To:
unknown-recipients:;" and "To: ietf-announce:;".
mail receivers should be able to parse groups anyway, since they want
to be able to read legacy messages.
this proposal strikes me as one of the form: since people won't adhere
to RFC X, presumably because they don't bother to read it fully, let's
write RFC Y that tells them to do something else. surely it's harder
to read and adhere to the combination of both RFCs X and Y?
particularly when they give conflicting advice?
and as long as we're trying to fix mailers, why not fix them to have
more utility? unless we believe that it's the humans who can't deal
with groups. (but as far as I can tell, humans seem to understand the
concept better than mailers).