It is very difficult to compare the model in detail with the model described in this thesis because ``A similarity between Penman's revision module and the model described in this paper is that neither has been implemented.'' ([Vaughan and McDonald1986], page 95). Although Meteer Meteer:90 gives a detail description of the relationship between text structure and revision it is unclear how the proposed model could contribute to the choice problem of paraphrases (see section 5.2). However, from the approach described above and from the system described in [Meteer1990] we can draw the following conclusions. Only the generator's input is marked. If the generator encounters alternative realizations the revision component is asked to make the decision. However, to be able to do this it needs detailed knowledge about the grammar. Therefore grammatical knowledge has to be duplicated. The linguistic realization component used in [Meteer1990] is MUMBLE-86 [McDonald1986]. The text structural representation level must completely specify the information to be expressed by the utterance. The mapping has to ensure that all the necessary linguistic information is present. Mumble's procedural grammar is used only for generation purposes. Therefore it is without reach for the revision model to take into account relevant sources of ambiguities.