Re: [xml-dev] Restrictions on existence of attributes?

[Michael Champion <mchampion@xegesis.org>]

Rick Jelliffe wrote:
> Stan Kitsis wrote:
>> In my experience API-level support is an order (or two) of magnitude 
>> more expensive than delivering UI apps.  First of all, the testing 
>> costs are much higher.  Second (and way more significant), once we 
>> realease an API, we will have to support it for 10 years or so - and 
>> this is extremely expensive.
>>   
> I hadn't heard that applications with User Interfaces were so cheap 
> and easy to deliver.
Note that Stan stressed the second point, that Microsoft shipped APIs 
have to be supported more or less forever, so the up front test costs 
are enormous.   If we're talking about RNG, I can very easily see the 
costs in the multiple millions of dollars -- for test case writing,  
implementation on .NET and native platforms,stress testing, performance 
tuning, extensive security scrutiny, integration with the rest of the 
stack, documentation for mainstream audiences, and so on.  Reasonable 
people inside and outside MS disagree on whether this is an appropriate 
commitment to quality / security / customer value or process overkill, 
but it's the world that Stan and I live in. For better or worse, that 
cost has to be balanced against both the actual customer benefit from 
supporting yet another XML technology, and the opportunity cost of not 
investing the resources in something that people really are clamoring for.

>   And I think customers would respond positively to MS and other 
> vendors supporting ISO Schematron, because it both fills a common and 
> constant need and because it increasingly is being adopted in 
> government and industry standards. Schematron is moving from being the 
> secret weapon of system developers, such as freight companies and 
> legal publishers, to being the way that organizations and consortia 
> who are serious about interoperability specify executable constraints 
> with user-focused diagnostics.
 I agree with all these points.  I encourage people who hit the wall 
with XSD in the Microsoft environment to try out Schematron constraints, 
use the reference XSLT implementation,  and see if that works for them.