The need for a cautious interpretation of results from an analytic method for an analysis of the stability of tidal inlets is illustrated by comparing theory with data from St. Andrew Bay in Florida's panhandle. Historically this bay was connected to the Gulf of Mexico by East Pass at the eastern end of the bay. However, following the opening of St. Andrew Bay Entrance in 1934 at the western end to serve Panama City, the flow cross-section of this channel increased while East Pass contracted gradually and eventually closed in 1998. In December 2001 East Pass was reopened by dredging a small flow-relief channel. These events provided the opportunity to apply the stability analysis to the newly-formed two-inlet one-bay system. Interpretation of the results in terms of observed inlet stability versus prediction is shown to be contingent upon knowledge of the history of channel maintenance and the morphodynamics of the bay. The illustration underscores the need to apply the method in pre-project engineering investigations of the long-term impact of opening a second inlet in a bay.