Scenario Frames for Guidance

When I tackle a problem domain, I first frame out the space.  To do this, I list out scenarios and sub-scenarios.  I group the scenarios under categories.  Sometimes categories come first, sometimes scenarios do.  I call the result, a Scenario Frame.

I use Scenario Frames to evaluate platform, tools, and guidance.   I also use them for product design, innovation, competitive assessments, subject matter expert reviews, arch and design reviews, and as a way to build shared understanding of a problem space.

Here's a Scenario Frame Example my team is creating to enumerate and evaluate Source Control scenarios in VSTS 2005:

What's your favorite tool for framing out problem spaces?