One of the reasons l= came to be was that we wanted to have as many valid signatures out there as quickly as possible, so as to provide a reasonable alternative basis for reputation. There was the presumption that the mailing list software would lag, and it has. Now we know that one MAJOR piece of mailing list software can be made to behave, and we know how to accommodate it if it doesn't. But in order to preserve the signature, everyone would essentially have to start using l=. I think that is the real question on the table, as to whether that is advisable. There are legitimate reasons to say that it is, and other reasons to say that it is not.
Eliot _______________________________________________ NOTE WELL: This list operates according to http://mipassoc.org/dkim/ietf-list-rules.html