discovery

Requirements, risks, architectures, strengths, weaknesses, proficiency, and throughput are examples of project and team elements that emerge or are discovered in an agile process.

unencumberment

Either get out of the way of X or keep Y out of your way. Remove anything that hinders your workflow and the progress and success of the project.

feedback

An agile process provides constant feedback along many dimensions of the project. This may take the form of an XP team's velocity, dependencies during refactoring from unit tests, Scrum Burndown Chart, or the frequent evaluation of software by the customer from frequent iterations.

sustainable, consistent pace

The month sprint of scrum, 40-hour XP workweek are examples.

synergy

The practices support each other. For example, collective code ownership and pair programming support each other in XP.

Besides the "by definition" consideration, existing agile processes, such as XP and Scrum, fit the above guidelines. I have not used Mary Poppendieck's Agile Customer Toolkit or Lean Software Development Toolkit, nor have I been part of a Feature Driven Development project, though I think they also conform to my guidelines.

Furthermore, I think the agility of an agile process is a measure of how the process contributes to the efficiency and productivity of the project and team. This contribution doesn't imply success, but should promote speed and responsiveness.

Unfortunately, I think it is very hard to measure agility; it is inherently qualitative and context biased . For example, I have always felt that Feature Driven Development isn't as agile as XP. I think the reason is one of encumberment. The documentation and project mangement aspects of FDD seem to encumber the project. However, you can make the argument that FDD may better promote the process of discovery and management, from the customer's perspective. XP provides little guidance for the customer as to the discovery of stories that provide the greatest business value.

I feel these guidelines offer a different perspective than the elements of the manifesto. For example, communication and collaboration are desirable because they promote discovery and provide feedback. As I consider the experiences I would characterize as "agile", I am better able to articulate their "agility" in terms of these guidelines.

Armed with this idea, I will now reconsider my thoughts on such questions as "what is Agile Testing?"