>This is easier to understand if you think of it in terms of set construction
>and iterators. The two expressions with abbreviations eliminated are:
>
>/descendant-or-self::node()/para[1]
>/descendant::para[1]
You might ask why // means the first of these, rather than the more
obvious second. The answer (I think) is precisely so that expressions
like //para[1] will mean what they do; it's more common to want to
treat the first paragraph in each section specially than the first
paragraph in the while document.
-- Richard
