Steve, any progress on providing a sanitized version? I have exact same issue as you do - and for me, the worst part is that I'm fairly new to Tableau. I'm hoping to learn by looking at your example. Thanks.
I apologise in advance for my not providing a sanitised version; I've just finished this role with one company and moved to a different role with a new firm.
I shall endeavour to get the sanitised version up before the year is out
I am really sorry about this, seemed to get swept away under HUGE workloads.
I shall get this posted by 27.07.2012
I'm sorry, I never did manage to get these uploaded; saying this, I believe that this has now been superseded by a possible solution in Tableau 8.
Whilst untested, it may be possible to use custom-sql with parameters to create pre-filtered sets and then to blend these with the original sources.