Thanks for that. It's really interesting and I will certainly "pinch" the idea for some project but it may not answer exactly my current problem.
The documentation I am looking for should cover both the Datamart(s) and OLAP levels as well as (if possible) help some avanced users build their own queries.
Although we don't know yet which tool the users would use for querying, I need to try and explain how they should join tables/views, etc.
Ideally, sprinkling a few pictures in the middle to make the relationships more intuitive.
Maybe a mixture of Visio/Excel/Sharepoint would work...