RE: [Bug 4675] add text in section 5.3.3 to require that consumers and producers are required to implement at a minimum the uri scheme

Forgive me, but:

>This is a "traditional view" in
>that all other standards (at least the ones I worked on) seem to share
>this understanding.  Thus, we have "interop" sessions to insure that the
>spec is written in sufficient specificity to insure that conformance
>results in interoperable implementations.

is to me a gross over-statement.  XML Schema and WS-Addressing are the two 
that leap to mind, since SML has made me more familiar with them.  Even 
very foundational things like RFC 3986 (URI syntax) do not on their own 
give you useful interop.  While it might be the original intent to make 
conformance = wide interop, if experience has shown me anything it is the 
trade-off between those two and spec writers rarely if ever have the 
prescience to anticipate all the holes in any natural language.  The more 
deeply you read existing standards, the more unspecified corners you 
usually find...some intentional, others not.  While it is common to assume 
that something we don't know deeply does make conformance = wide interop 
(assuming wide adoption, of course, else it's not "useful" interop), one 
thorough read is usually enough remedial education. 

I think we have "interop sessions" to ensure that _where conformance is 
intended to specify interop_, that this is in fact true.  Not to prove 
that the two are equal.  Saying that the two are equal is close to saying 
conformance allows zero implementation choices.

My approach in suggesting the change was simply to get back to the 
conformance definition the wg had already agreed to, and to (separately) 
acknowledge the effect of areas already in the spec on interop (_none_ of 
which was new), so we can get to Last Call in the same century as the 
schedule articulated in the charter.  Since I had discussed the draft with 
Sandy and Valentina before it was submitted (and missed this subtlety 
myself then), I know it was not their intent either to change the wg's 
already agreed to definition of conformance or to add a new linkage 
between conformance and choices that effect interop.  As noted in several 
calls, there are implementation choices - points where we consciously 
chose to make things optional - which will affect the degree of interop a 
given implementation exhibits.  The degree of practical interop 
demonstrated by any implementation is contingent in those cases not only 
upon the choices made by one implementation, but also by other 
implementations' choices and the adoption of each. 

I continue to see value in defining conformance as we have it now, and in 
giving implementers the information they need to make informed choices 
about the degree of interop they are guaranteed by the existing spec's 
MUSTs vs its MAYs.

Best Regards, John

Street address: 2455 South Road, P328 Poughkeepsie, NY USA 12601
Voice: 1+845-435-9470      Fax: 1+845-432-9787