We are creating a new protocol. We don't expect any current reader to behave well with it before it is done.
Quoting from RFC 2119, which is what we are using to define MUST and SHOULD:
6. Guidance in the use of these Imperatives
Imperatives of the type defined in this memo must be used with care and sparingly. In particular, they MUST only be used where it is actually required for interoperation or to limit behavior which has potential for causing harm (e.g., limiting retransmisssions) For example, they must not be used to try to impose a particular method on implementors where the method is not required for interoperability.
Why is the alternate link "actually required for interoperation or to limit behavior which has
potential for causing harm (e.g., limiting retransmisssions)"?
It seems like a perfect candidate for MAY, like most of the rest of the format.
--Paul Hoffman, Director --Internet Mail Consortium
