Title: Primer uses an assertion for MTOM that does not exist

Description: 

The primer utilizes MTOM Serialization assertion. There are several problems with this assertion. These problems make the assertion use by a reference inappropriate

Although the serialization optimization has been defined by XMLP wg, the WS-Policy assertion appears to exists only in products privately. The definition of the assertion is not available. Therefore, its scope and subject is not known. 

The primer uses the assertion reference & namespace in a localized fashion only to define Optional Assertions in Section 2.6 and Appendix B. 

Justification: 

In order for the Primer to "refer" to an assertion and use it, the assertion should be available or it should be defined. 

Proposal: 

There are three options: 

-- Owner(s) of the assertion may consider submitting to w3c as a contribution to generate a stable URI for reference. 

-- The Primer document can define the Assertion and its scope as an illustrative example. 

-- Since the utility of the mythical MTOM assertion in the referred chapter is to illustrate optional assertion use, instead WS-RMP defined by OASIS WS-RX tc can be used. Its semantics/ scope is available and it is also used with optional="true" attribute. 

Pros/Cons: 

Since MTOM serialization optimization capability is a general requirement, defining it just in the Primer document will not enable its reuse. Submission of the MTOM assertion could enable its general use, not as an illustration for WS-Policy, but it may take time. 

Without the presence of a stable URI and definition of MTOM assertion, my preference is 3.