The agilists I think ended up having pretty good answers for finding a sweet spot between small iterations that maintained quality while minimizing Big Design Upfront to prevent spending a lot of time preplanning the software, allowing a well functioning agile team to maintain reasonably high quality, extensibility, maintainability and satisfaction of actual customer needs while keeping velocity high and not getting bogged down in design heavy tar pits which were ended up not fully anticipating problems encountered during actual execution.
If that doesn't sound like a buzzword filled sentence I never expected to come out my mouth... But. The bottom line is: if you can keep your execution goals small and focused enough, you can iterate quickly towards a design with better information than you would have if you were to do a design study because you'll be better informed by the actual needs of the execution process than by what you _think_ the execution process will require at design time.