For yacht designs earlier than around 1985 the full stability curve will almost never be available. If the design is more recent, say after 1990 or so, and has been modeled by computer, the hydrostatics and stability analysis will usually have been performed by the computer. Any more, it is assumed that this information will be provided and that it will be thorough. To judge adequacy of stability is a complex matter. While relatively easy to assess and therefore tempting as a simple method, this is not a complete or necessarily adequate picture.
Stability is a dynamic event and is affected by quite a number of different vessel parameters.
The DSF is the result of work done by Moon and Oossanen to propose a rational criteria based an a number of factors that contribute to a vessel's sea keeping ability. Second, the DSF method was then expanded to include input from designers world wide and a refined method derived. The results of this research have been presented by Oossanen in a publication of the Chesapeake Sailing Yacht Symposium. Although the STIX formulae differ completely from those used by the DSF method, the STIX method takes a similar approach. While many other criteria have been proposed, the DSF and STIX methods are by far the most comprehensive, and provide the greatest amount of information about a sailing vessel's dynamic behavior.