I occasionally (and usually accidentally) find myself in a discussion about whether or not every story should be a shippable increment of work. The short answer is - Ideally, every user story is independently shippable.
The Experiment Canvas
In the past few years, we at OnBelay have had the honor of working with companies who are looking to improve their engineering culture.
One key tool we use today is the Experiment Canvas. My partner, Diane Zajac, and I co-developed the canvas. It is based heavily on our experience with A3s. It is still a work in progress, but I want to share with you where we are to date. Please feel free to use it and give us feedback.