The feedback loop is missing.  They view the stories as a spec that has been handed down.  And they have not made the connection that spec writing is design work that is intended to clearly illustrates concepts in a domain.  It is a form of writing code.  But it’s just that this code is, maybe, non-executable.

Here’s my workflow and how I close the loop.

• write story and scenario
• Sketch a design if needed – helps when pairing to be on the same page.
• Start writing test for scenario
• ooops … test is getting complicated? stuck?
• maybe the domain is not understood enough? Dig deeper, improve scenario, design (as needed) and continue writing test
• or maybe the scenario was badly written? Ignore scenario structure, continue writing test.  Refactor scenario later.  We’re in deep discovery mode here.
• get test to pass
• refactor code
• refactor scenario
• … cycle the red-green-refactor until happy.

Acknowledging when you’re in discovery mode and knowing that you are allowed to refactor requirements is the trick.  Nothing is cast in concrete.  That’s why I like frequent feedback loops with tight turning circles.

No feedback loop, no progress.

BTW, I really don’t like explaining such things as flow-charts and sequences.  You got to find your own style.  It’s not a recipe or rules thing.  The above is something that is about as close to what I do but it changes when the need arises.  That’s also another key feature of being agile – adapt or die in the waterfall.