I worked on a project a few years ago where the project requirements were in a Business Requirements Specification (BRS). The end result is usable, but it's difficult to get value from it - all the information is in the system, but bringing it together is tricky.
Had the requirements been defined in user stories/use cases, then I believe that the end result would have been much better. (It's important to note that the project was run in a waterfall fashion, so the users didn't see it until it was complete and that was too late...)
I can really see how analyzing a requirement/issue/project focusing on use and purpose rather than discrete functionally makes such a difference to the end result. Requirements analysis is still necessary - but it should be in context of use.