--On Thursday, April 03, 2008 09:16:58 AM -0400 Barry Leiba
<leiba(_at_)watson(_dot_)ibm(_dot_)com> wrote:
Don't pick at that -- it's just an example. The point is that we can't
anticipate all the issues that might arise. We can just say MUST when
we're defining something that will break interoperability if it's not
followed, and SHOULD or MAY otherwise. For most of these fields, there's
NO GOOD REASON to use MUST. There just isn't.
So we SHOULDN'T.
Again, this is exactly right. SHOULD is much stronger than people give it
credit for, and MUST is properly used very sparingly. If breaking a
requirement would cause problems with interoperability, security,
correctness, uncontrolled congestion on the Internet, etc, then MUST is
appropriate. Otherwise, it really is not.
-- Jeff