> At this point we're stuck because the requirements aren't clear.
> In the example, 12 appeared in the output before 11, but we
> don't know why: there was nothing in the requirements
> statement that said it should.

The only requirement is for the longer strings to come first.

So any of these results would be fine:

12|11|10|9|8|7|6|5|4|3|2|1
11|12|10|9|8|7|6|5|4|3|2|1
10|11|12|9|8|7|6|5|4|3|2|1
12|11|10|1|2|3|4|5|6|7|8|9
...

What is the simplest XPath expression to achieve that result?

/Roger