Currently, we can set to show concept description and concept id for the form field when it is a question. However, it doesn't show concept description and concept id for the form field answers.
Since paper form and computer screen have limited space, we usually have different text display on the paper form and computer screen than what we use for concept names. In AMPATH, we create something called "form key" which we have all the concept ids mapped to the text on the paper form.
On InfoPath Design, we are able to get the concept id info from the task pane or property of the object. It would be extremely helpful if we can have something similar in xforms.