Prior to those modern AMO standards you link to Brandon, the old bowyers used the measurement that Dave talks about. You measured from nock to nock across the belly of the bow. The bow braces on the belly side. Most everything you see now in print has been abridged and changed to suit modern bows and to kind of dumb-down the information to make it more understandable I suppose.
I'm the kind of person who likes the old measurements: Draw length....to back of bow. Bow weight...weight of bow drawn with arrow head to back of bow. Bow length....measurement from string nock to string nock across belly of bow. Simple, accurate, effective and non-ambiguous.