J.D. Meier posted some guidance on authoring prescriptive guidance modules for Guidance Explorer:
He also has a post that provides some general guidance on writing prescriptive guidance:
For those who don't know him, J.D. has been the program manager (PM) for security and performance on the patterns & practices team, which is now part of the larger Team System family. Chances are you've read quite a bit of the content he developed. I first worked with J.D. when writing the "abilities" content found in the Visual Studio .NET 2003 product documentation.