How to run multiple parameters per Loop in a Report Book?

Hi all:

Looking for advice on how to implement multiple parameters in a report book.  The standard loop functionality does not meet current needs.  Our reporting requires a user to specify 3 UD's to report out their area of responsibility.  Each user will have multiple sets of 3 UD's to generate all of their reports.  In theory, they need to 'loop over' this set of parameters generating reports for each set.  However, the standard loop functionality is only 1 parameter and nested loops will generate unnecessary combinations as it would be the cartesian product of all parameters.

Example:

 

Anyone have suggestions on how to implement this?  Is there a way to call a BR from the report book to substitute multiple variables at a time?

I envision the ideal state as:

• User populates a simple CSV file with their report sets consisting of a name, UD2, UD3, UD4, and owner
• User opens the report book
• User selects their report set CSV file
• The report book loops over each set (of multiple parameters) generating any # of reports using these parameters

Any suggestions are appreciated.

Thanks,

Dave