Martin (1992: 559):
Not in passing that wave patterns are very commonly reflected in the labelling given to beginning and end stages across genres, reflecting the peaks and troughs of prominence that open and close a text; a number of these are reviewed in Table 7.17.
Table 7.17 Culminative prominence and generic structure
beginning(initial prominence) end(final prominence) Mitchell (1957) Auctioneer’s Opening Conclusion Hasan (1977) Greeting Summary ^ Finis Hasan (1985) Sale Initiation Purchase Closure Hasan (1984) Initiating Event Finale Ventola (1979) Greeting Leave-taking ^ Goodbye
As the table demonstrates, this claim is wholly bogus. Not one of the labels "reflects" the notion of a wave peak or trough.