[security-services] schemaLocation in SAML schemas/docs

Hi,
This may be a stupid XML question but I have some problems
understanding why a line like the SAML assertion-schemas'

     schemaLocation="draft-sstc-schema-assertion-25.xsd"

makes any sense.

W3C's WSDL does not have such declarators neither in the schema or in the
sample instance-documements to take an example of a recent XML schema-
based standard.

That you need this when editing with XML Spy is for sure (as it does
not seem to support schema caching), but how useful is a local file-reference
in a real implementation?

BTW, does SAML instance documents need schemaLocations as well?

Personally, I think schemaLocations should be removed as all reasonable
XML systems support schema caching.

Anders R