> This gets my vote, as it's obviously the real problem.  It's foolish
> to assume that any one transport will be appropriate for everyone.

So, to be correct, every Unix MUA has to be aware of every Unix MTA?

/usr/{sbin,lib}/sendmail is the standard way of sending mail under
Unix.  /usr/bin/mail does not implement an SMTP client, and it
shouldn't.  When vi wants to tell you about a lost mail message, it
doesn't have to know about N different transports to do so.  So why,
just because a package happens to be called "mh" or "nmh", is it
suddenly appropriate to know about a million different ways of
injecting a message into SMTP-land?