XSLT: question re testing for possibly empty elements

Hi,

I'm working on someone else's code at the moment, and the author uses 
this construction very often:
<xsl:when test="string-length(anElement) &gt; 0">
statements
<xsl:otherwise>
'else' statements

I *think* what he's trying to do is to test if anElement is empty or 
not, and act accordingly.
But couldn't you rewrite that as

<xsl:when test="anElement">
...
<xsl:otherwise>
...

(as someone suggested a few threads ago)?

Or does the string-length() method check for something that the second 
method doesn't cover?
Thanks,
Ralph