Recommendation R.11

       Add the following sentences to the note:

       "Pending further study and more specific advice, arithmetic  addition  of
distortion can be safely assumed for simplicity in all cases. Although pessimistic 
this will not lead to unnecessarily restrictive planning decisions in those cases 
where there is a regenerative link in the chain, e.g., Recommendation R.101 TDM or a 
regenerative SPC exchange. However, where another law is known to apply then the 
appropriate law of addition can be used.

e.g.:
      mcvft           - see text of Recommendation above

      code-independent tdm-see note above for non-synchronized tandemed systems

                      - for synchronized tandemed systems the distortion due 
                        to the multiplexing process will be that of a single 
                        system

      code-dependent tdm-regenerative"