Now, in my project I have around 300 items, and I need to pair each
item with four of the other items randomly, and I will have to do that
many times a day.

I only need one seed, but I will have to make 300 transformations
every time a need to get the items "paired", so XSLT looks like not
being an option.

So far I have used C# calling a shuffle routine again and again in
other parts of the project, and I have a feeling that I will have to
continue doing it that way. Turns out to be one of the few things
being too nasty in XSLT in my particular use case.

Cheers,
Jesper