8. A method according to claim 1 , further comprising the step of: generating additional information that is not displayed to the user and that enables changes to the documents to result in corresponding changes to the model.
8. A method according to claim 1 , further comprising the step of: generating additional information that is not displayed to the user and that enables changes to the documents to result in corresponding changes to the model. 9. A method according to claim 8 , wherein said additional information includes information concerning a portion of the document and includes: an identifier of the model element represented, or a name of a property whose value is represented, or a type of model element to be created when adding another model element, or a type of relationship to create and a model element identifier of a peer model element to relate to when adding another new or existing model element, or an arbitrary command to be offered as an operation in a pop-up menu for that portion of the document.