I always find this kind of clue difficult. If you take the letters of "a young man to go" from "money" and "a stout waggon" you get ESTW - in order -WEST. The definition is in the whole of the clue, &lit http://www.crosswordunclued.com/2011/01/composite-anagrams.html
I think it's when you have to determine which letters are in the anagram (i.e. not just a list of letters or some words to rearrange, but you have to take certain letters from each of the words in the clue - perhaps?)
I always find this kind of clue difficult.
If you take the letters of "a young man to go" from "money" and "a stout waggon" you get ESTW - in order -WEST.
The definition is in the whole of the clue, &lit
http://www.crosswordunclued.com/2011/01/composite-anagrams.html