&gt; It certainly appears similarly, but the dependency and ordering primitives are interpreted much more loosely like tags than they are like absolute requirements.<p>Ah. <i>That</i> would be the &quot;subtlety&quot; that I was missing. Thanks! :)<p>As an aside: how terrible it is to provide an interface that makes it <i>look</i> it gives you ordering guarantees when -in actuality- it gives you no such thing! :(