Weak Validation

I have put a little note "Weak Validation" under

http://www.ascc.net/xml/en/utf-8/schemas.html

for your consideration.

It proposes that weaker but still useful (and easy to
implement) schemas can be extracted from content
models (in whatever syntax). 

Weak validation may have attractive properties for
implementors, flat database records, and XML
documents with arbitrarily pasted elements.

Rick Jelliffe