Here is a great interview of Alan Cooper, the designer of Visual Basic & Visual Studio and the author of the Goal-Driven Design (GDD), a close relative to the GUIDe by Sari A. Laakso:
http://www.infoq.com/interviews/Interaction-Design-Alan-Cooper
Agile is not about productivity, it’s about the core of motivation of the developers. The traditional management of the software projects usually lack understanding what is going on, set unrealistic objectives, drive for low quality and make the work of the developers miserable. While the industrial-era management doesn’t really understand what’s going on, the developers have filled out the vacuum by managing themselves. Instead, the knowledge workers are not motivated by money or following the schedules, but doing good (or great) work. Thus the rise of the Open Source, over there people can do as good products as they wish 🙂 If the industrial management techniques makes this impossible by managing the knowledge workers as industrial workers, then the developers are not pleased either. Because nobody is really managing the development work, the Agile has risen from the ranks of the developers to fix the management problem.
Alan Cooper claims that the process of the interaction design is quite similar to the agile ways. The key process is to reflect on the business problem before day zero of the start of the development. The key thing is to have deep and profound understanding of the business process.
Tasks are not Goals
The important thing is not what tasks the users do, but what is the end state. The design process is to redesign the tasks so that the goals can be achieved easier. By designing based on the tasks the result will be a Dancing Bear :). It dances, but not very prettily. The objective of the interaction design -school / GDD / GUIDe is to make the bear to dance well!
In software there is no economics of scale
In the old times the main driver of the business was to get the unit costs down. However, in the software industry the maintenance costs are zero or very low, but the development cost is rather high. The economics of the software are profoundly different to the economics of the manufacturing. Driving the cost down just drives down the desirability of the design. The most important thing is to worry how you can elevate your number one goal. The business managers should think only about how to increase the business value and quality instead of reducing the cost.