Dated1,
I'm fairly convinced the subject of a possible "stretching the glide" will be included in the accident report. As I see it, the report may suggest one of three things:
a) do nothing;
b) recommend additional flight crew training for handling low-level double engine failure;
c) recommend improved autopilot designs that automatically trim the plane for optimum glide range when sensing a power loss situation.
Each of the alternatives need to be judged on basis of the resulting increase in safety compared to the probability of this type of engine failure, as well as the implementation costs. Also we have to await the outcome of the search for the primary engine failure reason. In case that is not found, the case for doing something (b or c) becomes stronger.