It looks to me like the replacement set is incorrectly configured:

<replacement>

       <pat>SS2K5<pat>

       _{SQL Server 2005}

       _{SQL Server 2K5}

<replacement>

The closing </replacement> and </pat> tags are missing the '/'.

Here is a way to do it without any self joins.  It actually returns the last occurrence of the maximum vol instead of the first, but this should be OK as...