DR MichaelG, I listened carefully to both Lawrence recordings several times. I also worked for the Ira Gershwin estate on several projects, including assisting Michael Tilson Thomas on the Gershwin Centennial Celebration at the Brooklyn Academy of Music, a production of Strike Up the Band, directed by a jerk Gary Davis in Pasadena, 1988 (I think) and a revival of Oh, Kay! at Goodspeed, either before or after - who remembers now? - that Pasadena production.
Until I was unceremoniously sacked by another jerk and supposed friend in a 1991 power struggle inside Roxbury Recordings, I had been the primary editor of the first recording Girl Crazy. My last project with the Gershwins and Library of Congress, Life Begins at 8:40, was equally disastrous.