> Thanks for your input. What little I know about using "//" is 
> that the processor checks a whole document when a "//element" 
> is used. If we are talking about a really big document (few 
> mB) this would definitely slow down the transformation 
> processing time.
> 
> Right?

Not necessarily. With Saxon, using //x acts as a signal to build an index.
If you use the construct repeatedly, you might well get better performance
than when using /x/y/z - it all depends. Most XML databases will also use
indexes to implement //x efficiently.

The key to all performance improvement is measurement. Don't try to make any
improvements to your code until you have a measurement framework in place.
Once you've got proper instrumentation, you can experiment with code changes
to your heart's desire; without it, you're groping in the dark.

Regards,

Michael Kay
http://www.saxonica.com/
http://twitter.com/michaelhkay