[xsl] XPath equivalence question

[Graydon <graydon@xxxxxxxxx>]

Does 

<xsl:template match="/A//B">

match exactly the same thing as

<xsl:template match="B[/A]">?

My presumption is that the second form is preferable on efficiency
grounds -- on simple table lookup versus whatever tree-structure the
descendant axis search produces -- but I don't actually know.

-- Graydon