xsl:for-each with [not(@Name=preceding::*/@Name)] not working

[ksampson]

I'm at a loss here.

I need to loop through a bunch of nodes, but not nodes with repeating
attribute names.

I've created sample data, and it works fine with syntax like:

<xsl:for-each select="yada/yada/yada[not(@Name=preceding::*/@Name)]">
...
This works fine with my sample test XML, but not with my production
XML.

Basically, the production data gives back no Nodes. It filters all the
nodes out.

I tested the XPath without the [not(@Name=preceding::*/@Name)], and it
returns several nodes.