Interesting articles by Joel. I think his spreadsheets would be good input for a project manager to create a project schedule from. I worked with a development manger who used similar spreadsheets. Project is easier to show the effects of slipage on the end dates and lets users see what is happening.

As far as the users never knowing what they want -it depends upon the users. ultimately they need prototypes and will change their mind – that is part of the process. But becoming or having a subject matter expert as part of the project is the key. Whether that person is part of the development team officially or not his participation will enable a succesful development effort.