I have worked with several teams using Specification by Example with Concordion. We train our entire team to write Concordion specifications in HTML. Only a small subset of HTML is required, so we can train the beginner in about 30 minutes. Usually we have testers who write the HTML specification when BA or Scrum Master sometimes write them.
We used Eclipse (Web Page Editor) to edit HTML. This works well, except Concordion requires valid XHTML, and Eclipse does not allow validation of HTML as XHTML. This basically shows that the tags are used <br>, and not <br / ">. We consider this in training. We also train the whole team in using source control. Using Eclipse, we have one user interface for editing and source control We also find that having a team using the same IDE is a step towards a cross-functional team.
I know another team where BA writes specifications using a Mac-based HTML editor.
The concordion is actively maintained, quickly responding to the mailing list (Yahoo) and the list of problems. Concordion's code base is stable. Active development over the past year or so has focused on the expansion mechanism, allowing users to add commands and listeners (for example, to capture screenshots when the test fails).
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