<Alt-P> is used to trigger the 'p'rocessing of the conditional text in the underlying document  'Conditional text,' in turn, are those options, optional and repeat text block that you have previously marked up for processing when the document assembly routine is initiated.

   'P'rocessing is automatically invoked (so you don't have to press <Alt-P) when:

       you recall a document from a DropDown List or

you recall a document from an <Alt-G> call and the document is being called from the first line of an otherwise blank document.