I think Ariba is working on developing the ability to handle more than 1,000 items within an RFX document, and when that is available you should be able to build scenarios to analyze those responses. Currently, we are looking at other solutions to provide this time of scenario analysis and bid optimization, which will augment our esourcing work with Ariba.
Unfortunately, we don't support this in the solution currently. You can export to excel and do the analysis. I like the idea and would be a nice addition to the solution, please submit an ER and explain the use cases and benefits to your organization. Thank you!