On 02:15 07/09/02, Sally Floyd said: >For example, about layering, I think that layering is sometimes one of the >properties that allows complexity with robustness instead of fragility, >and that very careful, explicit, and conscious communication between >layers, when necessary, might be one of the strategies that allows >layering to work. The hourglass: layers above and below permit complexity while retaining core simplicity. May I add a comment to your document: a robustness aspect [you could point out as "communication between wg-layers"] is end to end lexical and grammatical consistency in their specifications. jfc