Enhance XLink: infer xlink:type

Obviously people feel XLink has too much syntax, and I'm pretty well 
convinced that they're right.  How about the following:

Make xlink:type inferrable from xlink:href as follows:

If an element has xlink:href=, then
- If its parent element has
   xlink:type="extended", infer xlink:type="locator"
- Otherwise infer xlink:type="simple"

Hey-presto, minimal simple xlinks are now
<foo xlink:href="bar">foo</foo> - no defaulting required!  Of course you 
could still put in xlink:title and other good stuff if you wanted.

Minimal extended xlinks become

<parent xlink:type="extended">
   <child xlink:href="audio.wav"/>
   <child xlink:href="text.html"/>
   <child xlink:href="vidio.mov"/>
   </parent>

  -Tim