Trevor,
the problem I see with Heidegger's account of death in relation to leading to the process of individuation and an authentic life is that few of us ever have the opportunity to face the possibility of death. Few of us are ever stranded in the Pilbara desert. Most Australians have never been there. Nor do they want to.

If we were in a war ---eg., like the diggers in the trenches in WW 1 or in the jungles in Vietnam----then we would expereince the possibility of death But few of us experience that these days in Australia; and most of us do not even come face to face with the possibility of our own death in the war on terror. The closest many of us come to the possibility of our own death is probably a car accident or cancer.

On Heidegger's account, that means only a few can live an authentic life from taking up the certainty of death. Most of us are fated to live an inauthentic life within convention and habit without ever being in a position to shape life of positive freedom through individuation.