quickstarts/switchyard/demos/helpdesk/Readme.md reads
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6. Going back to your web browser window:
    As krisv (a developer), click the Submit button to get the list of tasks.
    As krisv, review the tasks you want to perform and click the Submit button again.
    As david (a user), click the Submit button to get the list of tasks. He will only have tasks if more details were required.
    If there were user tasks, check the tasks you want to complete and click the Submit button again.
    Continue toggling back and forth as the users until all tasks are completed.
    You can view the application server output in its console window to see the progression of the progress.
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This is not valid, the ticket is immediately passed to the other user after the first click on Submit. So the users needs to switch in actions: krisv - david - krisv - david...